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Int J Mol Sci ; 22(14)2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34299005


Nanoparticles can interact with the complement system and modulate the inflammatory response. The effect of these interactions on the complement activity strongly depends on physicochemical properties of nanoparticles. The interactions of silver nanoparticles with serum proteins (particularly with the complement system components) have the potential to significantly affect the antibacterial activity of serum, with serious implications for human health. The aim of the study was to assess the influence of graphite oxide (GO) nanocomposites (GO, GO-PcZr(Lys)2-Ag, GO-Ag, GO-PcZr(Lys)2) on the antibacterial activity of normal human serum (NHS), serum activity against bacteria isolated from alveoli treated with nanocomposites, and nanocomposite sensitivity of bacteria exposed to serum in vitro (using normal human serum). Additionally, the in vivo cytotoxic effect of the GO compounds was determined with application of a Galleria mellonella larvae model. GO-PcZr(Lys)2, without IR irradiation enhance the antimicrobial efficacy of the human serum. IR irradiation enhances bactericidal activity of serum in the case of the GO-PcZr(Lys)2-Ag sample. Bacteria exposed to nanocomposites become more sensitive to the action of serum. Bacteria exposed to serum become more sensitive to the GO-Ag sample. None of the tested GO nanocomposites displayed a cytotoxicity towards larvae.

Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Grafite/química , Nanopartículas Metálicas/química , Nanocompostos/química , Óxidos/química , Soro/efeitos dos fármacos , Animais , Antibacterianos/química , Anti-Infecciosos/química , Sobrevivência Celular/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/efeitos da radiação , Humanos , Raios Infravermelhos , Larva/efeitos dos fármacos , Larva/efeitos da radiação , Lepidópteros/efeitos dos fármacos , Lepidópteros/efeitos da radiação , Nanopartículas Metálicas/administração & dosagem , Nanocompostos/administração & dosagem , Soro/microbiologia , Prata/química
Pathogens ; 10(1)2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33450948


Yersinia enterocolitica, widespread within domestic and wild-living animals, is a foodborne pathogen causing yersiniosis. The goal of this study was to assess a genetic similarity of Y. enterocolitica and Y. enterocolitica-like strains isolated from different hosts using Multiple Locus Variable-Number Tandem Repeat Analysis (MLVA) and Pulsed-Field Gel Electrophoresis (PFGE) methods, and analyze the prevalence of virulence genes using multiplex-Polymerase Chain Reaction (PCR) assays. Among 51 Yersinia sp. strains 20 virulotypes were determined. The most common virulence genes were ymoA, ureC, inv, myfA, and yst. Yersinia sp. strains had genes which may contribute to the bacterial invasion and colonization of the intestines as well as survival in serum. One wild boar Y. enterocolitica 1A strain possessed ail gene implying the possible pathogenicity of 1A biotype. Wild boar strains, represented mainly by 1A biotype, were not classified into the predominant Variable-Number Tandem Repeats (VNTR)/PFGE profile and virulotype. There was a clustering tendency among VNTR/PFGE profiles of pig origin, 4/O:3, and virulence profile. Pig and human strains formed the most related group, characterized by ~80% of genetic similarity what suggest the role of pigs as a potential source of infection for the pork consumers.

Curr Microbiol ; 77(9): 2166-2171, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32424607


Reptiles appear to be an important vector for Gram-negative pathogens, therefore, they are epidemiologically relevant. However, the composition of reptilian microbiota has been poorly recognized so far. The majority of studies concern exotic reptiles as asymptomatic carriers of Salmonella serovars. Studies of other intestinal bacteria of reptiles are rare. Only recently, the microbiota of free-living European reptiles have been investigated, however, on the basis of small samples, mainly in protected areas. Here, we aim to investigate cloacal Gram-negative microbiota of free-living Natrix natrix. Snakes (N = 45) used in the study were collected in Kraków (Poland) and its vicinity. Nineteen species of Gram-negative bacteria were isolated. The most common species were: Aeromonas hydrophila, Morganella morganii, Proteus vulgaris, Salmonella spp. The bacteria prevalent in N. natrix cloacal swabs are likely to represent the natural intestinal Gram-negative microbiota of the examined snakes. Importantly, the identified bacteria are pathogenic to humans, which clearly highlights the epidemiological potential of free-living N. natrix. The risk of infection is high for immunocompromised humans, children (under 5 years old), elderly persons, and pregnant women. Our study provides the largest dataset on intestinal Gram-negative microbiota of wild snakes. The presence of multiple human pathogens determined by us calls for the necessity of further studies on reptile-transmitted bacteria in anthropogenic environments.

Colubridae , Microbiota , Idoso , Animais , Criança , Pré-Escolar , Feminino , Humanos , Polônia , Gravidez , Salmonella
BMC Microbiol ; 18(1): 86, 2018 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-30119648


BACKGROUND: Yersinia enterocolitica is widespread within the humans, pigs and wild boars. The low isolation rate of Y. enterocolitica from food or environmental and clinical samples may be caused by limited sensitivity of culture methods. The main goal of present study was identification of presumptive Y. enterocolitica isolates using MALDI TOF MS. The identification of isolates may be difficult due to variability of bacterial strains in terms of biochemical characteristics. This work emphasizes the necessity of use of multiple methods for zoonotic Y. enterocolitica identification. RESULTS: Identification of Y. enterocolitica isolates was based on MALDI TOF MS, and verified by VITEK® 2 Compact and PCR. There were no discrepancies in identification of all human' and pig' isolates using MALDI TOF MS and VITEK® 2 Compact. However three isolates from wild boars were not decisively confirmed as Y. enterocolitica. MALDI TOF MS has identified the wild boar' isolates designated as 3dz, 4dz, 8dz as Y. enterocolitica with a high score of matching with the reference spectra of MALDI Biotyper. In turn, VITEK® 2 Compact identified 3dz and 8dz as Y. kristensenii, and isolate 4dz as Y. enterocolitica. The PCR for Y. enterocolitica 16S rDNA for these three isolates was negative, but the 16S rDNA sequence analysis identified these isolates as Y. kristensenii (3dz, 4dz) and Y. pekkanenii (8dz). The wild boar' isolates 3dz, 4dz and 8dz could not be classified using biotyping. The main bioserotype present within pigs and human faeces was 4/O:3. It has been shown that Y. enterocolitica 1B/O:8 can be isolated from human faeces using ITC/CIN culturing. CONCLUSION: The results of our study indicate wild boars as a reservoir of new and atypical strains of Yersinia, for which protein and biochemical profiles are not included in the MALDI Biotyper or VITEK® 2 Compact databases. Pigs in the south-west Poland are the reservoir for pathogenic Y. enterocolitica strains. Four biochemical features included in VITEK® 2 Compact known to be common with Wauters scheme were shown to produce incompatible results, thus VITEK® 2 Compact cannot be applied in biotyping of Y. enterocolitica.

Técnicas de Tipagem Bacteriana/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Sus scrofa/microbiologia , Suínos/microbiologia , Yersinia enterocolitica/isolamento & purificação , Animais , DNA Ribossômico , Reservatórios de Doenças/microbiologia , Fezes/microbiologia , Humanos , Polônia , Reação em Cadeia da Polimerase/métodos , RNA Ribossômico 16S/genética , Análise de Sequência , Especificidade da Espécie , Yersinia/classificação , Yersinia/genética , Yersinia/isolamento & purificação , Yersinia enterocolitica/classificação , Yersinia enterocolitica/genética