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Staphylococci are a natural component of the skin microbiota of many organisms, including humans and birds. As opportunistic pathogens, they can cause a variety of infections in humans. The close contact between domestic pigeons and their owners provide an opportunity for exchange of skin-associated bacteria. In this study, 41 healthy racing pigeons were tested. Staphylococci were detected on the skin of each bird (41/41, 100%). Isolates were identified at the species level using matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS). The diversity of the Staphylococcus species was relatively high and coagulase-negative staphylococci (CoNS) were predominantly isolated. In total, ten different staphylococcal species were identified. S. lentus (19/41, 46.3%) was noted most frequently. The pigeon skin was also inhabited by S. xylosus (6/41, 14.6%), S. equorum (4/41, 9.8%), S. hyicus (3/41, 7.3%), S. intermedius (2/41, 4.9%), S. sciuri (2/41, 4.9%), S. vitulinus (2/41, 4.9%), S. lugdunensis (1/41, 2.4%), S. hominis (1/41, 2.4%), and S. auricularis (1/41, 2.4%). Our results indicate that domestic pigeons may carry pathogens with zoonotic potential. All strains were susceptible to 12 antibiotics (ciprofloxacin, clindamycin chloramphenicol, erythromycin, fosfomycin, gentamicin, levofloxacin, norfloxacin, rifampicin, tobramycin, trimethoprim/sulfamethoxazole, vancomycin) representing 8 different classes. None isolate displayed a multidrug-resistant phenotype. Resistance to tetracycline (6/41, 14.6%) and to penicillin (4/41, 9.7%) was shown. The mecA gene was not detected in the examined strains and no methicillin-resistant staphylococci were found on the skin of the healthy pigeons. [ABSTRACT FROM AUTHOR]

Celem badań była ocena patogeniczności izolatów Plasmodiophora brassicae Wor. pobranych z porażonych kiłą roślin kapusty głowiastej białej pochodzących z różnych rejonów Polski. Oceniano wirulencję siedmiu izolatów tego patogena. Do określenia wirulencji izolatów P. brassicae użyte zostały obiekty wzorcowe, były to materiały hodowlane kapusty głowiastej białej odporne i podatne na kiłę. Nasiona kapusty inokulowano poprzez moczenie ich w zawiesinie zarodników przetrwalnikowych patogena. Ocenę podatności roślin na kiłę prowadzono w oparciu o 9-cio stopniową skalę porażenia korzeni roślin w stadium ośmiotygodniowej rozsady i podczas jesiennego zbioru roślin na polu zainfekowanym P. brassicae. Izolaty pochodzące z Pobiednika i Goźlic były bardziej wirulentne. Izolat P z Pobiednika spowodował porażenie roślin odmiany ‘Kilaxy’ F1 co oznaczało przełamanie cechującej tę odmianę odporności na kiłę. Odmiana ta w stosunku do pozostałych izolatów potwierdziła swoją odporność. Wrażliwa linia HTM charakteryzowała się najwyższym stopniem porażenia. Odnotowano różny poziom wrażliwości na zastosowane izolaty pomiędzy liniami pochodzącymi z mających geny odporności odmian ‘Oregon123’ i ‘Badger Shipper’. Mniej podatna na zastosowane izolaty była linia ‘Oregon123’. Obserwowano wpływ zastosowanych do inokulacji nasion izolatów na reakcję na patogena dojrzałych roślin kapusty na polu kiłowym

The aim of the research conducted in 2007-2009 was the evaluation of the pathogenicity of eight Plasmodiophora brassicae Wor. isolates collected from clubroot-infested white cabbage growing in different areas of Poland. Breeding materials from white cabbage resistant and susceptible to P. brassicae were used for this purpose. Cabbage seeds were infected by submerging them into a spore suspension. The screening of plant clubroot resistance using a nine-degree scale based on root symptoms was carried out at the eight-week-old seedling stage and at harvest time on a field infected by P. brassicae spores - called the ‘death field’. Differences in the pathogenicity of the collected isolates were determined. Isolates from Szczecin, Ostromęczyn, Krojczyn and Maszkienice were defined as the most virulent. Plants of the ‘Kilaxy’ F1 white cabbage cultivar confirmed resistance to all isolates, while plants of the susceptible HTM line from the ‘Hitoma’ F1 white cabbage cultivar were characterised by the highest infestation level. The evaluation of adult plants in the field with high P. brassicae spore contamination confirmed seedling test results. Different susceptibility was observed between sub-lines from the ‘Oregon 123’ and ‘Badger Shipper’ cultivars with resistant genes. ‘Oregon 123’ sub-lines were less susceptible to applied isolates than ‘Badger Shipper’ sub-lines at both the seedling stage and during the field test. A double-stage plant screening to pathogen reaction caused the elimination of the most susceptible plants at the seedling stage. Plants with a certain resistance level were planted in the ‘death field’.

Pneumocystis jirovecii is an opportunistic fungus causing Pneumocystis pneumonia primarily in immunosuppressed patients. However, immunocompetent individuals may become colonized and, as asymptomatic carriers, serve as reservoirs of the pathogen. Moreover, these asymptomatic carriers are at higher risk of developing pneumonia if favorable conditions occur. This study aimed to determine the prevalence of P. jirovecii in patients with various pulmonary diseases and to characterize the genetic diversity of organisms circulating in the studied population. Bronchial washing specimens from 105 patients were tested for presence of P. jirovecii using nested polymerase chain reaction (PCR) targeting the mtLSU rRNA gene, as well as immunofluorescence microscopy. Multilocus sequence typing involving analysis of three loci— mtLSU rRNA, CYB, and SOD — was used for genotyping analysis. P. jirovecii DNA was detected in 17 (16.2%) patients. Amplification of the SOD locus was successful only in five cases (29.4% of the positive patients), while mtLSU rRNA and CYB were genotyped in all positive samples. Therefore, combined genotypes were identified based only on mtLSU rRNA and CYB loci. Eight different genotypes were identified, with Pj 1 and Pj 2 being the most prevalent (29.4% of patients each). There was no statistical correlation between these genotypes and demographic or clinical data; however, we found that infection with mutant CYB strains occurred only in patients diagnosed with lung cancer. Of the potential predictors examined, only immunosuppressive treatment was significantly associated with colonization. In conclusion, patients with various respiratory diseases, especially when immunosuppressed, are at risk of Pneumocystis colonization. [ABSTRACT FROM AUTHOR]