Background: Allergic contact dermatitis (ACD) is an inflammatory skin disease caused by repeated skin exposure to contact allergens. The severity and duration of this disease are associated with many different factors. Some of these factors may represent markers for monitoring disease activity and the individual response to an intervention. Methods: We used a targeted metabolomics approach to find such factors in the serum of individuals with ACD. Metabolomics profiles were examined and compared in the acute phase of the disease and also in the absence of disease activity. Results: Our study identified a significant remission phase of ACD-associated systemic biochemical shifts in 2 metabolic pathways: tryptophan-kynurenine and phenylalanine-tyrosine. Conclusions: Although the responsible mechanisms are unclear, these results suggest that the remission phase of ACD is linked to tryptophan metabolism via kynurenine and phenylalanine-tyrosine pathways. However, further replication studies with a larger number of subjects and their subgroups are necessary to validate our results. These studies may provide a new perspective with which to understand the mechanism of and find potential biomarkers of ACD, as well as a new reference for personalized treatment.

Electroporation is an electric field induced phenomenon occurring when the permeability of the cell membrane is increased due to the excess of critical transmembrane potential. Fluorescent dye assays are frequently used for evaluation of the permeabilization rate, however, the protocols vary, which negatively affects the repeatability of the results. In this work we have designed experiments to investigate the protocols and threshold concentrations of the Propidium Iodide (PI) and YO-PRO-1 (YP) fluorescent dyes for evaluation of mammalian cell permeabilization induced by electroporation. The Sp2/0 mouse myeloma cells were used and the bursts of 100 μs × 8 electrical pulses of 0.8-2 kV/cm were applied. It has been shown that the dye concentration has an influence on the detectable permeabilization, and the concentrations below 30 μM for PI and 1 μM for YP should be avoided for measurement of electropermeabilization efficacy due to unreliable fluorescence signals. Further, based on the experimental data, the permeabilization curve for the Sp2/0 myeloma cells in the 0.8-2 kV/cm range has been presented.

The skin of persons with atopic dermatitis (AD) is very susceptible to cutaneous infection, and some yeast species may also aggravate AD. The total yeast population of an AD patient’s skin and its relation with individual age and body part remains poorly characterized. The aim of this study was to clarify the differences in cutaneous yeast flora by age and body parts of AD patients.By swabbing affected body parts (hands, legs, face, neck or trunk), 241 samples were collected from patients with AD (132 children and 109 adults), and as controls, 40 samples were taken from healthy individuals (20 children, 20 adults).In all, 89 (36.9%) of samples were positive; the yeast isolated belonged to three genera: Candida (27.4%), Malassezia (6.6%), and Rhodotorula (2.9%). Cutaneous colonization with yeasts was two-fold higher in the adults than in children (P<0.0001). The distribution of the yeast species was dependent on the body part sampled: Malassezia predominated in the face, neck, and trunk regions (P=0.0047); Candida more frequently colonized hands and legs (P=0.0029).Our study showed that cutaneous yeast flora and distribution of yeast species depends significantly on the age of the AD patient and the body part affected by atopic dermatitis.

Members of the yeast genus Malassezia, including atypical strains, are lipophilic except for Malassezia pachydermatis. New physiological features that characterize atypical Malassezia strains are mainly associated with alteration in Tween assimilation pattern — such isolates still require lipids for growth. We isolated three non-lipid-dependent strains of Malassezia from patients with diagnosed atopic dermatitis (AD). These isolates could not be identified to the species level via their physiological properties. Phylogenetic trees, based on the D1/D2 regions of the 26S rDNA gene sequences and nucleotide sequences of the ITS1-5.8S-ITS2 rRNA region, showed the isolates to belong to Malassezia furfur. Three non-lipid dependent isolates from AD skin were conspecific, and sequences analysis proved them to be M. furfur.