Native and designer cationic antimicrobial peptides are increasingly acknowledged as host defense molecules rather than true antimicrobials. Due to their ability to activate the innate immune system, these structures are used to treat uninfected and bacterially-infected wounds, including those harboring Acinetobacter baumannii. Previously we documented that when administered intramuscularly or topically in liquid formulations, the proline-rich host defense peptide dimer A3-APO accelerates uninfected wound re-epithelization and eliminates systemic and local A. baumannii, methicillin-resistant Staphylococcus aureus and other pathogen load from infected lesions better than conventional antibiotics. In the current study we sought to produce and characterize a novel delivery system, suitable for immediate and convenient application in non-hospital environments. The APO monomer was incorporated into polyvinyl alcohol nanofibers and the complex was polymerized into a solid patch dressing. Mice were subjected to skin abrasion where the wounds were either left uninfected or were inoculated with a near lethal dose of multidrug resistant A. baumannii strain. Analyzed after 3 days, APO monomer-containing patches improved wound appearance significantly better than polymer patches without antibiotics. When compared to colistin, the APO patches accelerated wound healing, and statistically significantly reduced wound size and wound bacterial load. The in vivo antimicrobial effect was more extensive than after intramuscular administration of the peptide drug, by using only one tenth of the active pharmaceutical ingredient. These data suggest that the APO monomer-impregnated nanofiber dressing can be developed as an economical first-line treatment option to skin injuries in general and battlefield burn and blast injuries in particular.

The marbled crayfish or Marmorkrebs, Procambarus fallax (Hagen, 1870) f. virginalis, a parthenogenetic freshwater crayfish belonging to the North American cambarids, was recorded in Hungary for the first time. Several specimens of this potentially invasive crayfish were caught at different locations in the thermal Lake Hévíz and its outflows in the western part of the country. Captured individuals covered a wide size range (5.5 to 50.5 mm carapace length) and one was carrying eggs and recently hatched offspring, which suggests that this organism has established a stable and self-sustaining population in the warm habitats of Lake Hévíz area. This finding is of great significance because these habitats belong to the catchment of the Danube River including Lake Balaton, and thus, a significant further spread of the marbled crayfish is likely to happen in Central Europe. Furthermore, the expansion of this crayfish already reached the Kis-Balaton, one of the landscape protection areas of the Balaton Uplands National Park, what could have currently yet unpredictable consequences for this unique wetland biotope.

The application of high-speed rotary spinning can offer a useful mean for either preparation of fibrous intermediate for conventional dosage forms or drug delivery systems. Polyvinylpyrrolidone (PVP) and poly(vinylpyrrolidone-vinylacetate) (PVP VA) micro- and nanofibers of different polymer concentrations and solvent ratios were prepared with a high-speed rotary spinning technique. In order to study the influence of parameters that enable successful fiber production from polymeric viscous solutions, a complex micro- and macrostructural screening method was implemented. The obtained fiber mats were subjected to detailed morphological analysis using scanning electron microscope (SEM), and rheological measurements while the microstructural changes of fiber samples, based on the free volume changes, was analyzed by positron annihilation lifetime spectroscopy (PALS) and compared with their mechanical characteristics. The plasticizing effect of water tracked by ortho-positronium lifetime changes in relation to the mechanical properties of fibers. A concentration range of polyvinylpyrrolidone solutions was defined for the preparation of fibers of optimum fiber morphology and mechanical properties. The method enabled fiber formulation of advantageous functionality-related properties for further formulation of solid dosage forms.

In 2017, the mysid Paramysis lacustris (Czerniavsky, 1882) was found for the first time in the Hungarian Danube section, representing the first psammo-pelophilous Ponto-Caspian peracarid colonizing the Middle Danube. In 2018, a brief survey focusing on this species revealed its presence in a more than 500-km-long river section spanning from Austria (Vienna, river km 1926) to Croatia (Batina, river km 1425). The largest populations of P. lacustris might be formed in reservoirs and slow-flowing stretches, where the appearance of the species might imply a considerable impact in connection with its zooplanktivorous feeding and important role in the diet of fish. Similar to all the other Ponto-Caspian peracarids that have crossed the Middle Danube, P. lacustris can reasonably be expected to continue its spread toward Western Europe in the future.

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