Differences in proteolytic activity and gene profiles of fungal strains isolated from the total parenteral nutrition patients

Fungal infections constitute a serious clinical problem in the group of patients receiving total parenteral nutrition. The majority of species isolated from infections of the total parenteral nutrition patients belong to Candida genus. The most important factors of Candida spp. virulence are the phenomenon of “phenotypic switching,” adhesins, dimorphism of fungal cells and the secretion of hydrolytic enzymes such as proteinases and lipases, including aspartyl proteinases. We determined the proteolytic activity of yeast-like fungal strains cultured from the clinical materials of patients receiving total parenteral nutrition and detected genes encoding aspartyl proteinases in predominant species Candida glabrata—YPS2, YPS4, and YPS6, and Candida albicans—SAP1–3, SAP4, SAP5, and SAP6. C. albicans released proteinases on the various activity levels. All C. glabrata strains obtained from the clinical materials of examined and control groups exhibited secretion of the proteinases. All 13 isolates of C. albicans possessed genes SAP1–3. Gene SAP4 was detected in genome of 11 C. albicans strains, SAP5 in 6, and SAP6 in 11. Twenty-six among 31 of C. glabrata isolates contained YPS2 gene, 21 the YPS4 gene, and 28 the YPS6 gene. We observed that clinical isolates of C. albicans and C. glabrata differed in SAPs and YPSs gene profiles, respectively, and displayed differentiated proteolytic activity. We suppose that different sets of aspartyl proteinases genes as well as various proteinase-activity levels would have the influence on strains virulence

Diversity of Staphylococcus aureus Isolates in European Wildlife

Staphylococcus aureus is a well-known colonizer and cause of infection among animals and it has been described from numerous domestic and wild animal species. The aim of the present study was to investigate the molecular epidemiology of S. aureus in a convenience sample of European wildlife and to review what previously has been observed in the subject field. 124 S. aureus isolates were collected from wildlife in Germany, Austria and Sweden; they were characterized by DNA microarray hybridization and, for isolates with novel hybridization patterns, by multilocus sequence typing (MLST). The isolates were assigned to 29 clonal complexes and singleton sequence types (CC1, CC5, CC6, CC7, CC8, CC9, CC12, CC15, CC22, CC25, CC30, CC49, CC59, CC88, CC97, CC130, CC133, CC398, ST425, CC599, CC692, CC707, ST890, CC1956, ST2425, CC2671, ST2691, CC2767 and ST2963), some of which (ST2425, ST2691, ST2963) were not described previously. Resistance rates in wildlife strains were rather low and mecA-MRSA isolates were rare (n = 6). mecC-MRSA (n = 8) were identified from a fox, a fallow deer, hares and hedgehogs. The common cattle- associated lineages CC479 and CC705 were not detected in wildlife in the present study while, in contrast, a third common cattle lineage, CC97, was found to be common among cervids. No Staphylococcus argenteus or Staphylococcus schweitzeri-like isolates were found. Systematic studies are required to monitor the possible transmission of human- and livestock- associated S. aureus/MRSA to wildlife and vice versa as well as the possible transmission, by unprotected contact to animals. The prevalence of S. aureus/MRSA in wildlife as well as its population structures in different wildlife host species warrants further investigation

Susceptibility testing of Aspergillus niger strains isolated from poultry to antifungal drugs - a comparative study of the disk diffusion, broth microdilution (M 38-A) and Etest methods

The aim of this study was to determine the sensitivity of Aspergillus niger strains isolated from birds to available antifungal drugs using different in vitro assays - classical disk diffusion, Etest® and broth microdilution NCCLS/CLSI M 38-A. The study material consisted of about 2.000 swabs and samples from different species of birds. A. niger (n=10) was accounted for 6.81% of the total pool of strains isolated. Determinations were made for 13 antifungal drugs using the disk diffusion method. The A. niger exhibited high susceptibility to enilconazole, terbinafine, voriconazole, tioconazole and ketoconazole, low susceptibility to clotrimazole, miconazole and nystatin, and resistance to amphotericin B, itraconazole, pimaricin, fluconazole and 5-fluorocytosine. Minimum inhibitory concentration (MIC) was determined for 9 antifungal drugs using the micromethod of duplicate serial dilutions in a liquid medium. A. niger strains were most susceptible to enilconazole and voriconazole. MIC ranged from 0.0625 to 0.5 μg/ml for enilconazole, with MIC90-0.5 μg/ml and MIC50-0.125 μg/ml. The corresponding values for voriconazole were 0.25-1 μg/ml, 1 μg/ml and 0.5 μg/ml. MIC for amphotericin B and terbinafine ranged from 0.5 to 4 μg/ml, while the values for the remaining drugs were highly varied. MIC was measured by the gradient diffusion method using Etest® for 5 antifungal drugs: amphotericin B, fluconazole, itraconazole, ketoconazole and voriconazole. By far the highest susceptibility was obtained in the case of voriconazole, with MIC ranging from 0.0625 to 1 μg/ml. MIC for amphotericin B ranged from 0.25 to 4 μg/ml, for itraconazole and ketoconazole ranging from 0.5 to 16 μg/ml. Methods available for this purpose are not always applicable in field conditions. The present results indicate that the Etest® technique, due to its high percentage of agreement with the M 38-A microdilution method, should find application in medical and veterinary practice

Zmiany aktywności fosfatazy zasadowej w wodzie litoralnej Jeziora Piaseczno (Pojezierze Łęczyńsko-Włodawskie) w latach 1996-2016 jako wskaźnik przeobrażeń środowisk wodnych na terenach rolniczych

Between 1996 and 2016 the activity of alkaline phosphatase in the littoral water of Lake Piaseczno was researched in fiveyear measurement cycles. Samples of water from the area corresponding to the agricultural sector of the lake catchment area were used as the research material. Simultaneously, the content of nitrogen and phosphorus compounds in the soils of the agricultural sector of Lake Piaseczno was investigated. Between 1996 and 2006 the activity of alkaline phosphatase in the water under study was similar and exhibited a slight increasing tendency. In the consecutive measurement cycles (2011 and 2016) the activity of the enzyme in the water increased significantly. The research also proved that every year the content of mineral forms of nitrogen and assimilable phosphorus in the soil surrounding the lake tended to increase. The enzymatic parameter under study was used as an indicator of lake eutrophication. The research revealed that during the period under analysis the trophicity of Lake Piaseczno increased.W latach 1996-2016, w 5-letnim cyklu pomiarowym, badano aktywność fosfatazy zasadowej w wodzie litoralnej Jeziora Piaseczno. Obiektem badań były próbki wody pochodzące z obszaru odpowiadającego sektorowi rolniczemu zlewni jeziora. Równolegle badano także zawartość związków azotu i fosforu w glebach przybrzeżnych sektora rolniczego Jeziora Piaseczno. W latach 1996-2006 aktywność fosfatazy zasadowej w badanych wodach utrzymywała się na zbliżonym poziomie, wykazując niewielką tendencje wzrostową. Natomiast w kolejnych cyklach pomiarowych (2011 i 2016) zanotowano istotny wzrost aktywności tego enzymu w badanej wodzie. Wykazano także wzrastającą z roku na rok zawartość mineralnych form azotu i fosforu przyswajalnego w glebie przybrzeżnej jeziora. Opierając się na badanym parametrze enzymatycznym jako jednym ze wskaźników eutrofizacji jezior stwierdzono, że w analizowanym okresie wystąpił wzrost troficzności zbiornika Piaseczno