Search

Your search keyword '"Železnik Ramuta, Taja"' showing total 2 results
Start Over Author "Železnik Ramuta, Taja" Topic electron microscopy
2 results on '"Železnik Ramuta, Taja"'

1. The antibacterial activity of human amniotic membrane against multidrug-resistant bacteria associated with urinary tract infections

Author

Železnik Ramuta, Taja, Tratnjek, Larisa, Janev, Aleksandar, Seme, Katja, Starčič Erjavec, Marjanca, and Erdani-Kreft, Mateja

Subjects
udc:616.6, antibiotic resistance, antimicrobial activity, electron microscopy, urothelial cells, homogenat amnijske membrane, amniotic membrane homogenate, multidrug-resistant bacteria, MRSA, biochemical phenomena, metabolism, and nutrition, bacterial infections and mycoses, urinary bladder, odpornost na antibiotike
Abstract

Urinary tract infections (UTIs) represent a serious global health issue, especially due to emerging multidrug-resistant UTI-causing bacteria. Recently, we showed that the human amniotic membrane (hAM) could be a candidate for treatments and prevention of UPEC and Staphylococcus aureus infections. However, its role against multidrug-resistant bacteria, namely methicillin-resistant S. aureus (MRSA), extended-spectrum beta-lactamases (ESBL) producing Escherichia coli and Klebsiella pneumoniae, vancomycin-resistant Enterococci (VRE), carbapenem-resistant Acinetobacter baumannii, and Pseudomonas aeruginosa has not yet been thoroughly explored. Here, we demonstrate for the first time that the hAM homogenate had antibacterial activity against 7 out of 11 tested multidrug-resistant strains, the greatest effect was on MRSA. Using novel approaches, its activity against MRSA was further evaluated in a complex microenvironment of normal and cancerous urinary bladder urothelia. Even short-term incubation in hAM homogenate significantly decreased the number of bacteria in MRSA-infected urothelial models, while it did not affect the viability, number, and ultrastructure of urothelial cells. The hAM patches had no antibacterial activity against any of the tested strains, which further exposes the importance of the hAM preparation. Our study substantially contributes to basic knowledge on the antibacterial activity of hAM and reveals its potential to be used as an antibacterial agent against multidrug-resistant bacteria.

Published
2022

2. A Biomimetic Porcine Urothelial Model for Assessing Escherichia coli Pathogenicity.

Author

Predojević, Luka, Keše, Darja, Žgur Bertok, Darja, Železnik Ramuta, Taja, Veranič, Peter, Erdani Kreft, Mateja, and Starčič Erjavec, Marjanca

Subjects
ESCHERICHIA coli, URINARY tract infections, UROTHELIUM, TRANSMISSION electron microscopy, FOOT & mouth disease
Abstract

Urinary tract infections can be severe, sometimes fatal, diseases whose etiological pathogens are predominantly uropathogenic strains of E. coli (UPEC). To investigate the UPEC pathogenesis, several models have already been established with minor or major disadvantages. The aim was to develop a simple, fast, and inexpensive biomimetic in vitro model based on normal porcine urothelial (NPU) cells that are genetically and physiologically similar to human bladder urothelium and to perform basic studies of E. coli pathogenicity. Initially, the model was tested using a set of control E. coli strains and, subsequently, with human E. coli strains isolated either from patients with urinary infections or from the feces of healthy individuals. A drop in viability of NPU cells was used as a measure of the pathogenicity of the individual strain tested. To visualize the subcellular events, transmission and scanning electron microscopy was performed. The strains were tested for the presence of different virulence-associated genes, phylogroup, type of core lipid, O-serotype, and type of lipopolysaccharide and a statistical analysis of possible correlations between strains' characteristics and the effect on the model was performed. Results showed that our model has the discriminatory power to distinguish pathogenic from non-pathogenic E. coli strains, and to identify new, potentially pathogenic strains. [ABSTRACT FROM AUTHOR]

Published
2022
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results