Publications by authors named "Agnieszka Torzewska"

A phage-antibiotic synergy could be an alternative in urinary tract infection (UTI) therapy, as it leads to the elimination of bacteria and to the reduction in variants resistant to phages and antibiotics. The aims of the in vitro study were to determine whether phages vB_Efa29212_2e and vB_Efa29212_3e interact synergistically with selected antibiotics in the treatment of infections, to optimize antibiotic concentrations and phage titers for the most effective combinations, and to assess their impact on the number of spontaneous resistant variants and on the phages' reproductive cycles. The modified double-layer disc diffusion method, checkboard, time-kill assays, one-step growth method and the double agar overlay plaque assay were implemented.

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Taking into account that in recent decades there has been an increase in the incidence of urinary stones, especially in highly developed countries, from a wide range of potentially harmful substances commonly available in such countries, we chose zinc for the research presented in this article, which is classified by some sources as a heavy metal. In this article, we present the results of research on the influence of Zn2+ ion on the nucleation and growth of struvite crystals-the main component of infection urinary stones. The tests were carried out in an artificial urine environment with and without the presence of Proteus mirabilis bacteria.

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urinary tract infections can lead to serious complications such as development of urinary stones. spp., belonging to the natural microbiota of the urinary tract, exhibit a number of antagonistic mechanisms against uropathogens, including the secretion of organic acids.

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Infectious urolithiasis is a type of urolithiasis, that is caused by infections of the urinary tract by bacteria producing urease such as Proteus mirabilis. Lactobacillus spp. have an antagonistic effect against many pathogens by secreting molecules, including organic acids.

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In this paper, we present the results of research on the physicochemical properties of two selected faces of the struvite crystal, which is the main component of infectious urinary stones. Two main faces, (001) and ([Formula: see text]), ending the c-axis, were selected for the study. These faces are not related by symmetry relations, which means, among other things, that they should have a different atomic structure, which was confirmed experimentally.

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The natural microbiota of the urinary tract includes spp., which secrete molecules with antimicrobial properties and have antagonistic activity against many pathogens. This paper focuses on the antibacterial effect of strains isolated from urine against clinical strains of isolated from kidney stones and from urine with coexisting urolithiasis.

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In recent years, there has been a continuous increase in the incidence of urolithiasis, especially in highly developed countries. Therefore, the question arises which factors specific to these countries may be responsible for the increase in the incidence of this disease. In this article, we try to assess the effect of phosphoric acid, a component of various carbonated drinks, including Coca-Cola, on the nucleation and growth of struvite crystals, which are the main component of infectious urinary stones.

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Proteus mirabilis is a common cause of infectious urolithiasis. The first stage in the formation of urinary stones is the crystallization of mineral salts in the urine induced by urease activity of this microorganism. Lactobacillus spp.

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Poorly crystalline and amorphous precipitate (PCaAP) is one of the components of the so-called infectious urinary stones, which are the result of the activity of urease-producing microorganisms, mainly from the Proteus species, in particular Proteus mirabilis. The main component of this kind of stones is crystalline struvite (MgNHPO∙6HO). Bacteria can build into the structure of the urinary stone and, in this way, they are one of the components of the urinary stone.

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Infectious urolithiasis is a consequence of long-standing urinary tract infections with urease-positive bacteria, especially Proteus spp. However, because of the often mixed nature of urinary tract infections, in the case of urinary stones formation, several species of bacteria may be involved in the process. The purpose of the study was to determine the impact of the bacterial species: Escherichia coli, Klebsiella pneumoniae, Providencia stuartii, Pseudomonas aeruginosa and Staphylococcus aureus on the crystallization caused by Proteus mirabilis.

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Providencia is an opportunistic human pathogen that belongs to the Enterobacteriaceae family. The bacterial cell surface O-antigen is one of the most structurally variable cell constituents and serves as a basis for serotyping gram-negative bacteria. In this work, the genomes of 12 Providencia strains were sequenced, and genes driving O-antigen biosynthesis were analyzed.

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Proteus species are well-known opportunistic pathogens frequently associated with skin wound and urinary tract infections in humans and animals. O antigen diversity is important for bacteria to adapt to different hosts and environments, and has been used to identify serotypes of Proteus isolates. At present, 80 Proteus O-serotypes have been reported.

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Interleukin-8 (IL-8) has been implicated in the pathogenesis of several human respiratory diseases, including tuberculosis (TB). Importantly and in direct relevance to the objectives of this report quite a few findings suggest that the presence of IL-8 may be beneficial for the host. IL-8 may aid with mounting an adequate response during infection with Mycobacterium tuberculosis (M.

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Infectious urolithiasis is a result of recurrent and chronic urinary tract infections caused by urease-positive bacteria, especially Proteus mirabilis. The main role in the development of this kind of stones is played by bacterial factors such as urease and extracellular polysaccharides, but urinary tract environment also contributes to this process. We used an in vitro model to establish how the changes in the basic minerals concentrations affect the intensity of crystallization which occurs in urine.

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Infectious urinary stones account for about 10% of all urinary stones. In 50% of cases urolithiasis is a recurrent illness, which can lead to the loss of a kidney if not properly treated. One of the reasons for recurrence of the disease may be the ability of bacteria to invade urothelial cells, persist in the host cells and serve as potential reservoirs for infection.

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Microorganisms are one of the important factors for urinary calculi formation. While urease-positive bacteria and nanobacteria contribute to stone formation, Oxalobacter formigenes rods play a protective role against the development of urolithiasis. Proteus mirabilis alkaline environment of the urinary tract and cause crystallization mainly of struvite (magnesium ammonium phosphate).

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Infectious urolithiasis is a consequence of persistent urinary tract infections caused by urease producing bacteria e.g. Proteus mirabilis.

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Proteus mirabilis cause urinary tract infections which are recurrent and can lead to formation of urinary calculi. Both bacterial and the host factors are involved in the development of urolithiasis. To determine the impact of glycosaminoglycans (GAGs) in the formation of P.

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The objectives of the investigation presented in this paper were: to examine the frequency of P. mirabilis isolation from catheters and assess the complexity of multi-species biofilms which these bacteria form, as well as to determine the vulnerability of planktonic and sessile P. mirabilis populations to popular antibiotics and compare it to the susceptibility of other Gram-negative bacteria isolated as associated flora from multi-species biofilm.

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Crystallization of struvite from artificial urine in the presence of Proteus mirabilis microorganisms depends strongly on pH value. At small value of pH, struvite yields crystals of coffin-like habit with very specific structure. The analysis using scanning electron microscopy shows that the crystals possess well-defined faces, but higher magnifications show very specific structuration as if the crystals were built from small three-dimensional subunits.

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We investigated the activity of curcumin against Proteus mirabilis and the struvite crystallization in relation to urinary stones formation. In order to evaluate an activity of curcumin we performed an in vitro experiment of struvite growth from artificial urine. The crystallization process was induced by Proteus mirabilis to mimic the real urinary tract infection, which usually leads to urinary stone formation.

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In the present work, we carried out density functional calculations of struvite--the main component of the so-called infectious urinary stones--to study its structural and elastic properties. Using a local density approximation and a generalised gradient approximation, we calculated the equilibrium structural parameters and elastic constants C(ijkl). At present, there is no experimental data for these elastic constants C (ijkl) for comparison.

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Crystallographic structure, total energy, electronic structure, and the most important elastic properties of struvite, NH(4)MgPO(4).6H(2)O, the main component of infectious urinary stones, are presented. The calculations were performed using ab initio full-electron calculations within the density functional theory-generalized gradient approximation (DFT-GGA) framework.

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The entry of Providencia alcalifaciens into the enterocyte-like cell line Caco-2 compared to HEp-2 was studied. Of the 22 P. alcalifaciens strains, 13 and 21 were invasive for Caco-2 and HEp-2 cells, respectively.

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