Building associated illnesses - sick building syndrome (SBS) as a common example - are associated with staying in buildings with poor indoor air quality. The importance of indoor fungal growth in this phenomenon continues to be evident, even though no causative relation has been established so far. Indoor humidity is strongly associated with the symptoms of SBS. Fungal metabolites that may induce ill health in susceptible occupants comprise beta-D-glucan, mycotoxins, and volatile organic compounds as known irritants and/or immunomodulators. Indoor toxic fungal metabolites might be located in micromycetal propagules (endometabolites), in (bio-)aerosol, detritus, and house dust (exometabolites) as their particular carriers. It is highly probable that hyphal fragments, dust, and particles able to reach the alveoli have the strongest depository and toxic potential. Most fungal spores are entrapped by the upper respiratory tract and do not reach further than the bronchi because of their size, morphology, and the mode of propagation (such as slime heads and aggreggation). This is why studies of the toxic effects of fungal spores prefer directly applying metabolite mixtures over mimicking real exposure. Chronic low-level exposure to a mixture of fungal toxicants and other indoor stressors may have synergistic effects and lead to severe neuroendocrineimmune changes.

There has been much more damage to forests in the Slovak Republic in the second half of the 20th century than to other European countries. Forested mountain massifs have become a filter of industrial and transportation emissions from abroad, as well as from domestic origins. There are not only acidic deposits of sulphur and heavy metals present in forest soils, but other additional environmental problems, such as climate change, storms, fires, floods, droughts, are worsening the situation. Therefore, forest terrestrial ecosystems are becoming more vulnerable due to changes in natural and environmental conditions. In the High Tatra Mountains in Slovakia, which are protected as a national park, four internationally monitored localities were established after the windthrow disaster in 2004 and fire in 2005: REF, with intact forest; EXT, with extracted wood mass; NEX, with non-extracted wood mass; and FIR, the burnt locality. Soils from these localities were microbiologically analysed with special attention to fungi. Bacterial microbiota detected by high-throughput sequencing showed the prevalence of the genera Acidothermus, Mycobacterium, and Nocardia, and a very low presence of the genera Acidibacter, Burkholderia-Paraburkholderia, Optitus and the uncultured genus Desulfurellaceae H16 in the soil sample from the burnt locality when compared with the unburned sites. Additionally, soil mycocoenoses showed a low similarity between the locality with an intact forest ecosystem and the localities with extracted (REF–EXT) and non-extracted (REF–NEX) wood mass. There was no similarity with the burnt locality (FIR), where heat-resistant fungi dominated. It was shown that the windthrow disaster and subsequent extraction or non-extraction of wood mass did not affect the soil microbial communities or their development. On the other hand, the influence of fire was significant.

Inflammatory and Haematotoxic Potential of Indoor Stachybotrys chartarum (Ehrenb.) Hughes Metabolites: MouldStachybotrys chartarum(Ehrenb.) Hughes is known to pose a health risk in indoor environments. Most of its strains can produce several intra- and extracellular trichothecene mycotoxins. Complex secondary metabolites of stachybotrys isolates from mouldy dwellings/public buildings in Slovakia were intratracheally instilled in Wistar male rats (4 μg in 0.2 mL of 0.2 % dimethylsulphoxide; diacetoxyscirpenol as the positive control). After three days, haematological parameters were measured in peripheral blood and inflammatory response biomarkers in bronchoalveolar lavage fluid (BALF), and the results were statistically analysed. Exometabolites proved to suppress red blood cell (RBC), decreasing the total RBC count, haemoglobin, and haematocrit. The exposed rats showed significantly higher total BALF cell count, indicating inflammation, lower alveolar macrophage counts, and increased granulocyte count related to the BALF cells. Due to haematotoxic and inflammation-inducing properties, metabolites ofS. chartarumcan cause damage to the airways and haematological disorders in occupants of mouldy buildings.

In the fight against antibiotic resistance, which is rising to dangerously high levels worldwide, new strategies based on antibiotic-conjugated biocompatible polymers bound to magnetic nanoparticles that allow the drug to be manipulated and delivered to a specific target are being proposed. Here, we report the direct surface engineering of nontoxic iron oxide nanoparticles (IONs) using biocompatible dextran (Dex) covalently linked to β-cyclodextrin (β-CD) with the ability to form non-covalent complexes with silver-sulfamethazine (SMT-Ag). To achieve a good interaction of β-CD-modified dextran with the surface of the nanoparticles, it was functionalized with diphosphonic acid (DPA) that provides strong binding to Fe atoms. The synthesized polymers and nanoparticles were characterized by various methods, such as nuclear magnetic resonance (NMR), Fourier transform infrared (FTIR) and ultraviolet–visible (UV–Vis) spectroscopies, transmission electron microscopy (TEM), thermogravimetric analysis (TGA), atomic absorption spectroscopy (AAS), dynamic light scattering (DLS), etc. The resulting magnetic ION@DPA-Dex-β-CD-SMT-Ag nanoparticles were colloidally stable in water and contained 24 μg of antibiotic per mg of the particles. When tested for in vitro antimicrobial activity on Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria and fungi (yeast Candida albicans and mold Aspergillus niger), the particles showed promising potential.