Loss of species and genetic diversity during colonization: Insights from acanthocephalan parasites in northern European seals.

Studies on host-parasite systems that have experienced distributional shifts, range fragmentation, and population declines in the past can provide information regarding how parasite community richness and genetic diversity will change as a result of anthropogenic environmental changes in the future. Here, we studied how sequential postglacial colonization, shifts in habitat, and reduced host population sizes have influenced species richness and genetic diversity of (Acanthocephala: Polymorphidae) parasites in northern European marine, brackish, and freshwater seal populations. We collected population samples from Arctic, Baltic, Ladoga, and Saimaa ringed seal subspecies and Baltic gray seals, and then applied COI barcoding and triple-enzyme restriction-site associated DNA (3RAD) sequencing to delimit species, clarify their distributions and community structures, and elucidate patterns of intraspecific gene flow and genetic diversity.

Trace elements in Ladoga ringed seal (Pusa hispida ladogensis) hair.

Hair samples of two adults, eight molted pups, and four newborn Ladoga ringed seals Pusa hispida ladogensis found stranded ashore on Lake Ladoga, North-West Russia, in 2020-2021, were analyzed for concentrations of trace elements, including toxic heavy metals. Al had the highest median concentration (9.25 μg/g, range 1.

4-Azidocinnoline-Cinnoline-4-amine Pair as a New Fluorogenic and Fluorochromic Environment-Sensitive Probe.

A new type of fluorogenic and fluorochromic probe based on the reduction of weakly fluorescent 4-azido-6-(4-cyanophenyl)cinnoline to the corresponding fluorescent cinnoline-4-amine was developed. We found that the fluorescence of 6-(4-cyanophenyl)cinnoline-4-amine is strongly affected by the nature of the solvent. The fluorogenic effect for the amine was detected in polar solvents with the strongest fluorescence increase in water.

DNA barcoding reveals different cestode helminth species in northern European marine and freshwater ringed seals.

Three subspecies of the ringed seal () are found in northeastern Europe: in the Baltic Sea, in Lake Saimaa in Finland, and in Lake Ladoga in Russia. We investigated the poorly-known cestode helminth communities of these closely related but ecologically divergent subspecies using COI barcode data. Our results show that, while cestodes from the Baltic Sea represent , all worms from the two lakes are identified as , a species that has previously not been reported from seals.

[In silico modeling of izoniazid-steroid conjugates interactions with cytochromes P450 of mycobacteria and their bioconversion in vitro by the cells].

Molecular docking of four hydrazones of isoniazid with steroids (dehydroepiandrosterone, pregnenolone, 16α,17α-epoxypregnenolone, cholestenone) - IDHEA, IPRE, IEP5, ICHN, to mycobacterial cytochromes P450 was performed. The in silico study has shown than these hydrazones can be effectively bound to CYP121, CYP124, CYP125, CYP126A1, CYP130, and CYP51 with binding energy ranged from -9 kcal/mol to -12 kcal/mol. Calculations also demonstrated enhancement of passive lipid bilayer permeability with respect to isoniazid.