Magnetic nanoparticles as a drug delivery system that enhance fungicidal activity of polyene antibiotics.

This study was designed to assess the antifungal/anti-biofilm and hemolytic properties of two polyene antibiotics, amphotericin B (AMF) and nystatin (NYS), attached to the surface of magnetic nanoparticles (MNP) against clinical isolates of Candida species and human red blood cells, respectively. The developed nanosystems, MNP@AMF and MNP@NYS, displayed stronger fungicidal activity than unbound AMF or NYS. Synergistic activity was observed with a combination of polyenes and MNPs against all tested Candida strains. Nanosystems were more potent than unbound agents when tested against Candida strains in the presence of pus, and as agents able to prevent Candida biofilm formation. The observed inactivation of catalase Cat1 in Candida cells upon treatment with the nanosystems suggests that disruption of the oxidation-reduction balance is a mechanism leading to inhibition of Candida growth. The significant decrease of polyenes lytic activity against host cells after their attachment to MNPs surface indicates improvement in their biocompatibility.

Environmental contamination with Toxocara eggs and seroprevalence of toxocariasis in children of northeastern Poland.

Toxocariasis is a worldwide distributed zoonotic disease. Soil contaminated with Toxocara eggs appears to be the main source of infection for humans. The aim of our study was to estimate the environmental contamination with Toxocara eggs in public areas in northeastern Poland followed by the assessment of seroprevalence of toxocariasis in the children's population inhabiting the areas. A total of 168 soil samples were collected in June and September from public areas, and 28 from patients' residences. They were all examined for Toxocara eggs using the centrifugal flotation technique. Two-step serological tests comprising enzyme-linked immunosorbent assay (ELISA) and Western blot (WB) were performed in 190 children aged 2-17 without any symptoms of toxocariasis. The positive samples accounted for 36 and 32 % in the urban area, 39 and 18 % in the suburbs, and 39 and 46 % in parks, for June and September, respectively. All the sites located near the patients' residences with confirmed persistent toxocariasis were found contaminated with Toxocara eggs. A significant drop in the mean number of eggs was noted in the suburbs after summer (0.64 vs 0.18, p < 0.05). High and constant contamination was documented in soil from urban sandboxes and parks. The overall seroprevalence in children tested for toxocariasis was 4.2 % as determined by ELISA and WB (3.0 % in preschool children and 7.7 % in school children). The current study revealed high contamination of public areas in northeastern Poland with Toxocara eggs as well as marked seroprevalence in asymptomatic children. There is an urgent need to introduce and promote preventive health measures to limit spread of toxocariasis.

Occurrence of fungi and fungus-like organisms in the Horodnianka River in the vicinity of Bialystok, Poland.

Studies of fungi and fungus- like organisms in the northeastern Poland have mainly concentrated on running waters in the vicinity of Bialystok, including the Horodnianka River. The main objective was to investigate biodiversity of fungi and fungus-like organisms which take part in decomposition of organic matter commonly found in inland waters. To obtain a complete picture of species composition of fungi and fungus-like organisms in running waters we decided to explore representative sites of the Horodnianka River such as Olmonty, Hryniewicze and Horodniany with close localization of landfill. Fungal species were isolated using baiting technique. Baits of onion skin (Alium cepa), hemp-seeds (Cannabis sativa), impregnated cellophane and snake skin (Natrix natrix) were applied to isolate fungi from water of the Horodnianka River. The fungal community consists of 26 species, 10 species of fungi belonging to class Chytridiomycetes (3), anamorphic fungi (6), and Zygomycetes (1). 16 species belong to fungus-like organisms from class Oomycetes. Most of the recognized species have already been found in other running waters. From all the examined habitats the fungi belonging to 26 species of 18 genera Achlya, Alternaria, Aphanomyces, Aspergillus, Catenophlyctis, Dictyuchus, Fusarium, Karlingia, Lagenidium, Leptomitus, Olpidiopsis, Penicillium, Phlyctochytrium, Pythium, Saprolegnia, Scoliognia, Thraustotheca and Zoophagus were obtained. Certain fungal species like Aphanomyces laevis, Fusarium aqueductum, F. moniliforme, F. oxysporum, Leptomitus lacteus, Saprolegnia feax and S. parasitica were found at all the study sites. Among fungi potentially pathogenic and allergogenic for humans the genera Alternaria, Aspergillus, Fusarium, Lagenidium and Penicillium have already been described. However, the species Lagenidium giganteum and Achlya androgyna are new in the fungal biota of Poland. The greatest number of fungal species occurred in Olmonty (24), the smallest in Horodniany (13). Presence of fungi such as Leptomitus lacteus, Fusarium aqueductum in the water of the Horodnianka River offers the possibility of using them as indicators of water quality.

[Water fungi occurence in the water reservoir in Zarzeczany of Podlasie province]. / Grzyby wodne wystepujace w zbiorniku wodnym w Zarzeczanach w województwie podlaskim.

Studies on the occurrence of aquatic microorganisms in the newest water reservoir Zarzeczany village were carried out in years 2001-2004. Hydro chemical analysis was performed using standard methods. Bait method was used to isolate the fungi. In the reservoir 52 fungi species were identified: fish pathogenic Achlya debaryana, A. polyandra, Aphanomyces laevis, Dictyuchus monosporus, D. sterile, Saprolegnia ferax, S. monoica, S. parasitica, human pathogenic Candida albicans, C. tropicalis and Trichosporon cutaneum, decomposing keratin Blastocladiopsis parva, Catenaria anguillulae, C. verrucosa, Catenophlyctis variabilis, Lagenidium humanum, Rhizophydium keratinophilum, and decomposing chitin Aphanomyces astaci, Karlingia chitinophila, Rhizidium chitinophilum, Asterophlyctis irregularis and Blastocladiella brytanica.

[Water fungi occurence in the River Suprasl-bath Jurowce near Bialystok]. / Grzyby wodne wystkpujace w rzece Suprasl-kapielisko Jurowce obok bialegostoku.

Studies on the occurrence of aquatic fungi in the bathing sites of the Suprasl River in Jurowce village were collected in years 2000-2003. Hydrochemical analysis was performed using standard methods. Bait method was used to isolate the fungi. In the Suprasl River at Jurowce village 36 fungi species were identified, among them fish pathogens Achlya orion, Aphanomyces laevis, Dictyuchus monosporus, Saprolegnia ferax, Saprolegnia monoica, S. parasitica, human pathogens Aspergillus flavus, Candida albicans, Lagenidium humanum, Penicillium mycetomagenum, Rhizophydium keratinophilum and Trichosporon cutaneum, phytopathogens Achlya racemosa, Phytophthora gonapodoides, Pythium butleri, P. myriotylum and P. debaryanum. Physicochemical parameters of waters in Suprasl River-bathing sites had no important effect on the occurrence of fungi.

[Candida albicans, Candida aquatica, Candida krusei and Candida tropicalis strains isolated from springs of Podlasie province]. / Szczepy Candida albicans, Candida aquatica, Candida krusei i Candida tropicalis izolowane ze zródel województwa podlaskiego.

Species composition of yeast-like fungi was investigated in 2001-2003 years. Four species from genus Candida were found: Candida albicans, Candida aquatica, Candida krusei and Candida tropicalis. The occurrence of yeast was investigated, using bait and the Sabouraud methods in the fresh waters of the six springs: Antoniuk, Cypisek, Sobolewo, Smolniki, Pólko and Rybnik of Podlasie Province. The fungi were found to be the most common at eutrophized sites of the spring Sobolewo. The spring Sobolewo, as compared to remaining springs, had a considerably higher concentrations of ammonium nitrogen, phosphates, and suspended substances.

[Occurrence and morphology of some predatory fungi, amoebicidal, rotifericidal and nematodicidal, in the surface waters of Bialystok region]. / Wystepowanie i morfologia niektórych drapieznych grzybów pelzako-, wrotko- i nicieniobójczych w wodach powierzchniowych okolic bialegostoku.

Studies concerned the occurrence of some predatory fungi in the surface waters: springs, rivers, lakes and ponds of Bialystok region, collected in years 1999-2002. The following species of predatory fungi, amoebicidal, rotifericidal and nematodicidal were found: Arthrobotrys oligospora Fresenius, Zoophagus insidians Somlnestorff, Somnuerstorffia spinosa Arnaudov, Dactylaria brochopaga Drechsler, Euryancale sacciospora Dreschler and Zoopage phanera Drechsler. Physico-chemical parameters of waters in basins and water-courses did not prove important effect on existence of fungi. A little more species of predatory fungi were recorded in samples of water in early spring and late autumn.

Zoosporic and conidial fungi within the Podlasie stretch of the river bug.

Zoosporic and conidial fungi species and environmental factors in 5 various sites of the Podlasie stretch of the river Bug were studied. Samples of water were collected in October 1999 and April 2000 for hydrochemical analysis and the order to determine the number of fungal species. Buckwheat-seeds, hemp-seeds, cellophane and snake exuviae were used as bait during the exposure in laboratory. Sixty-four zoosporic fungus species and forty-six conidial species were found in various sites of the Podlasie stretch of the river Bug. 8 species were recorded for the first time from Poland.

Further studies on aquatic fungi in the River Narew within the Narew National Park.

Zoosporic and conidial fungi species and environmental factors in 10 various sites of River Narew in the Narew National Park were studied. Samples of water were collected in autumn 1999 and spring 2000 for hydrochemical analysis and the order to determine the number of fungal species. Buckwheat-seeds, hemp-seeds, cellophane and snake exuviae were used as bait during the exposure in laboratory. 198 lower aquatic fungus species were found in various sites of River Narew. 13 species were recorded for the first time from Poland.

Occurrence of keratinophilic fungus Lagenidium humanum Karling in the surface waters of Podlasie.

The occurrence of keratinophilic fungus Lagenidium humanum Karling was investigated, using the bait method, in relation to the environmental conditions in the surface waters of the River Bug, Suprasl and Zwierzyniec in Podlasie in the years 1995-2000. The fungus was found to be the most common at eutrophized sites of the River Suprasl and Biala, and snake exuviae was the most frequently colonized bait. It was revealed that the occurrence of Lagenidium humanum in the water reservoirs was mostly affected by the content of biogenes, suspended solids, oxidability and temperature. Its appearance was seasonal, being most common in spring and autumn.

Accumulation and loss of Lindane in the muscles, liver and brain of some freshwater fish after intoxication with gamacarbatox suspension.

Experiments were conducted under laboratory conditions on young specimens of Carassius carassius L., Cyprinus carpio L. and on adult specimens of Leucaspius delineatus Haeckel. The fish were subjected to a 30-day exposure to gamacarbatox suspension in a dose of 0.5 mg 1-1, containing 10% of lindane as active substance. Directly after the experiment on day 30, and then 40 and 50, lindane content was assessed in the muscles, liver and brain using the method of gas chromatography with an electron capture detector. In all the fish examined, the highest accumulation of lindane and its longest duration were observed in the brain. Less lindane was noted in the liver. The lowest level of lindane was found in the muscles and its concentration in that tissue decreased most rapidly.