To trace evolution of Panton-Valentine leucocidin-positive clonal complex 398 methicillin-resistant Staphylococcus aureus (MRSA) in the Czech Republic, we tested 103 MRSA isolates from humans. Five (4.9%) were Panton-Valentine leucocidin-positive clonal complex 398, sequence types 1232 and 9181. Spread to the Czech Republic may result from travel to or from other countries.

• MeSH
• bakteriální toxiny * biosyntéza   genetika   MeSH
• dějiny 21. století MeSH
• dospělí MeSH
• exotoxiny * genetika   biosyntéza   MeSH
• leukocidiny * genetika   MeSH
• lidé MeSH
• methicilin rezistentní Staphylococcus aureus * genetika   izolace a purifikace   MeSH
• stafylokokové infekce * mikrobiologie   epidemiologie   MeSH
• Check Tag
• dějiny 21. století MeSH
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• historické články MeSH
• Geografické názvy
• Česká republika MeSH

Methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa are major causes of hospital-acquired infections and sepsis. Due to increasing antibiotic resistance, new treatments are needed. Mesenchymal stem cells (MSCs) have antimicrobial effects, which can be enhanced by preconditioning with antibiotics. This study investigated using antibiotics to strengthen MSCs against MRSA and P. aeruginosa. MSCs were preconditioned with linezolid, vancomycin, meropenem, or cephalosporin. Optimal antibiotic concentrations were determined by assessing MSC survival. Antimicrobial effects were measured by minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and antimicrobial peptide (AMP) gene expression. Optimal antibiotic concentrations for preconditioning MSCs without reducing viability were 1 μg/mL for linezolid, meropenem, and cephalosporin and 2 μg/mL for vancomycin. In MIC assays, MSCs preconditioned with linezolid, vancomycin, meropenem, or cephalosporin inhibited MRSA or P. aeruginosa growth at lower concentrations than non-preconditioned MSCs (p ≤ 0.001). In MBC assays, preconditioned MSCs showed enhanced bacterial clearance compared to non-preconditioned MSCs, especially when linezolid and vancomycin were used against MRSA (p ≤ 0.05). Preconditioned MSCs showed increased expression of genes encoding the antimicrobial peptide genes hepcidin and LL-37 compared to non-preconditioned MSCs. The highest hepcidin expression was seen with linezolid and vancomycin preconditioning (p ≤ 0.001). The highest LL-37 expression was with linezolid preconditioning (p ≤ 0.001). MSCs' preconditioning with linezolid, vancomycin, meropenem, or cephalosporin at optimal concentrations enhances their antimicrobial effects against MRSA and P. aeruginosa without compromising viability. This suggests preconditioned MSCs could be an effective adjuvant treatment for antibiotic-resistant infections. The mechanism may involve upregulation of AMP genes.

• MeSH
• antibakteriální látky farmakologie   terapeutické užití   MeSH
• antimikrobiální peptidy MeSH
• cefalosporiny farmakologie   MeSH
• hepcidiny farmakologie   terapeutické užití   MeSH
• lidé MeSH
• linezolid farmakologie   terapeutické užití   MeSH
• meropenem farmakologie   terapeutické užití   MeSH
• methicilin rezistentní Staphylococcus aureus * MeSH
• mezenchymální kmenové buňky * MeSH
• mikrobiální testy citlivosti MeSH
• Pseudomonas aeruginosa genetika   MeSH
• stafylokokové infekce * mikrobiologie   MeSH
• vankomycin MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

Nanoparticles have drawn significant interest in a range of applications, ranging from biomedical to environmental sciences, due to their distinctive physicochemical characteristics. In this study, it was reported that simple biological production of Ag, Se, and bimetallic Ag2Se nanoparticles (NPs) with Pseudomonas aeruginosa is a promising, low-cost, and environmentally friendly method. For the first time in the scientific literature, Ag2Se nanoparticles have been generated via green bacterial biosynthesis. UV-vis spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and EDX were used to characterize the produced NPs. Biosynthesized NPs were examined for antibacterial, antibiofilm, and photocatalytic properties, and it was determined that the effects of NPs were dose dependent. The biosynthesized AgNPs, SeNPs, and Ag2Se NPs showed anti-microbial activity against Escherichia coli and Staphylococcus aureus. Minimal inhibitory concentrations (MICs) of E. coli and S. aureus were between 150 and 250 μg/mL. The NPs showed antibiofilm activity against E. coli and S. aureus at sub-MIC levels and reduced biofilm formation by at least 80% at a concentration of 200 μg/mL of each NPs. To photocatalyze the breakdown of Congo red, Ag, Se, and Ag2Se NPs were utilized, and their photocatalytic activity was tested at various concentrations and intervals. A minor decrease of photocatalytic degradation was detected throughout the NPs reuse operation (five cycles). Based on the encouraging findings, the synthesized NPs demonstrated antibacterial, antibiofilm, and photocatalytic properties, suggesting that they might be used in pharmaceutical, medical, environmental, and other applications.

• MeSH
• antibakteriální látky * farmakologie   chemie   chemická syntéza   MeSH
• biofilmy * účinky léků   MeSH
• Escherichia coli * účinky léků   MeSH
• katalýza MeSH
• kovové nanočástice * chemie   MeSH
• mikrobiální testy citlivosti * MeSH
• Pseudomonas aeruginosa * účinky léků   metabolismus   MeSH
• selen chemie   farmakologie   MeSH
• sloučeniny stříbra chemie   farmakologie   MeSH
• Staphylococcus aureus * účinky léků   MeSH
• stříbro * chemie   farmakologie   metabolismus   MeSH
• technologie zelené chemie * MeSH
• Publikační typ
• časopisecké články MeSH

x

x

• MeSH
• exfoliatiny izolace a purifikace   škodlivé účinky   MeSH
• leukocidiny izolace a purifikace   škodlivé účinky   MeSH
• lidé MeSH
• polymerázová řetězová reakce MeSH
• septický šok etiologie   MeSH
• stafylokokové infekce * mortalita   MeSH
• Staphylococcus aureus * izolace a purifikace   klasifikace   MeSH
• Check Tag
• lidé MeSH
• Geografické názvy
• Česká republika MeSH

The aim of this study was to develop multifunctional magnetic poly(ε-caprolactone) (PCL) mats with antibacterial properties for bone tissue engineering and osteosarcoma prevention. To provide good dispersion of magnetic iron oxide nanoparticles (IONs), they were first grafted with PCL using a novel three-step approach. Then, a series of PCL-based mats containing a fixed amount of ION@PCL particles and an increasing content of ascorbic acid (AA) was prepared by electrospinning. AA is known for increasing osteoblast activity and suppressing osteosarcoma cells. Composites were characterized in terms of morphology, mechanical properties, hydrolytic stability, antibacterial performance, and biocompatibility. AA affected both the fiber diameter and the mechanical properties of the nanocomposites. All produced mats were nontoxic to rat bone marrow-derived mesenchymal cells; however, a composite with 5 wt.% of AA suppressed the initial proliferation of SAOS-2 osteoblast-like cells. Moreover, AA improved antibacterial properties against Staphylococcus aureus and Escherichia coli compared to PCL. Overall, these magnetic composites, reported for the very first time, can be used as scaffolds for both tissue regeneration and osteosarcoma prevention.

• MeSH
• antibakteriální látky chemie   farmakologie   MeSH
• Escherichia coli účinky léků   MeSH
• kosti a kostní tkáň MeSH
• krysa rodu rattus MeSH
• kyselina askorbová * chemie   farmakologie   MeSH
• lidé MeSH
• magnetické nanočástice chemie   MeSH
• nádorové buněčné linie MeSH
• nanokompozity chemie   MeSH
• osteoblasty metabolismus   cytologie   MeSH
• osteosarkom patologie   MeSH
• polyestery * chemie   MeSH
• Staphylococcus aureus * účinky léků   růst a vývoj   MeSH
• testování materiálů MeSH
• tkáňové inženýrství * MeSH
• tkáňové podpůrné struktury chemie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Staphylococcus aureus infections present a significant threat to the global healthcare system. The increasing resistance to existing antibiotics and their limited efficacy underscores the urgent need to identify new antibacterial agents with low toxicity to effectively combat various S. aureus infections. Hence, in this study, we have screened T-muurolol for possible interactions with several S. aureus-specific bacterial proteins to establish its potential as an alternative antibacterial agent. Based on its binding affinity and interactions with amino acids, T-muurolol was identified as a potential inhibitor of S. aureus lipase, dihydrofolate reductase, penicillin-binding protein 2a, D-Ala:D-Ala ligase, and ribosome protection proteins tetracycline resistance determinant (RPP TetM), which indicates its potentiality against S. aureus and its multi-drug-resistant strains. Also, T-muurolol exhibited good antioxidant and anti-inflammatory activity by showing strong binding interactions with flavin adenine dinucleotide (FAD)-dependent nicotinamide adenine dinucleotide phosphate (NAD(P)H) oxidase, and cyclooxygenase-2. Consequently, molecular dynamics (MD) simulation and recalculating binding free energies elucidated its binding interaction stability with targeted proteins. Furthermore, quantum chemical structure analysis based on density functional theory (DFT) depicted a higher energy gap between the highest occupied molecular orbital and lowest unoccupied molecular orbital (EHOMO-LUMO) with a lower chemical potential index, and moderate electrophilicity suggests its chemical hardness and stability and less polarizability and reactivity. Additionally, pharmacological parameters based on ADMET, Lipinski's rules, and bioactivity score validated it as a promising drug candidate with high activity toward ion channel modulators, nuclear receptor ligands, and enzyme inhibitors. In conclusion, the current findings suggest T-muurolol as a promising alternative antibacterial agent that might be a potential phytochemical-based drug against S. aureus. This study also suggests further clinical research before human application.

• MeSH
• antibakteriální látky * farmakologie   chemie   MeSH
• antioxidancia farmakologie   chemie   MeSH
• bakteriální proteiny antagonisté a inhibitory   metabolismus   chemie   MeSH
• fytonutrienty * farmakologie   chemie   MeSH
• lidé MeSH
• objevování léků * metody   MeSH
• počítačová simulace MeSH
• simulace molekulární dynamiky MeSH
• simulace molekulového dockingu MeSH
• stafylokokové infekce farmakoterapie   mikrobiologie   MeSH
• Staphylococcus aureus * účinky léků   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

Staphylococcus aureus, a notorious pathogen with versatile virulence, poses a significant challenge to current antibiotic treatments due to its ability to develop resistance mechanisms against a variety of clinically relevant antibiotics. In this comprehensive review, we carefully dissect the resistance mechanisms employed by S. aureus against various antibiotics commonly used in clinical settings. The article navigates through intricate molecular pathways, elucidating the mechanisms by which S. aureus evades the therapeutic efficacy of antibiotics, such as β-lactams, vancomycin, daptomycin, linezolid, etc. Each antibiotic is scrutinised for its mechanism of action, impact on bacterial physiology, and the corresponding resistance strategies adopted by S. aureus. By synthesising the knowledge surrounding these resistance mechanisms, this review aims to serve as a comprehensive resource that provides a foundation for the development of innovative therapeutic strategies and alternative treatments for S. aureus infections. Understanding the evolving landscape of antibiotic resistance is imperative for devising effective countermeasures in the battle against this formidable pathogen.

• MeSH
• antibakteriální látky * farmakologie   terapeutické užití   MeSH
• bakteriální léková rezistence MeSH
• lidé MeSH
• mikrobiální testy citlivosti MeSH
• stafylokokové infekce * farmakoterapie   mikrobiologie   MeSH
• Staphylococcus aureus * účinky léků   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

A series of new unique acetylene derivatives of 8-hydroxy- and 8-methoxyquinoline- 5-sulfonamide 3a-f and 6a-f were prepared by reactions of 8-hydroxy- and 8-methoxyquinoline- 5-sulfonyl chlorides with acetylene derivatives of amine. A series of new hybrid systems containing quinoline and 1,2,3-triazole systems 7a-h were obtained by reactions of acetylene derivatives of quinoline-5-sulfonamide 6a-d with organic azides. The structures of the obtained compounds were confirmed by 1H and 13C NMR spectroscopy and HR-MS spectrometry. The obtained quinoline derivatives 3a-f and 6a-f and 1,2,3-triazole derivatives 7a-h were tested for their anticancer and antimicrobial activity. Human amelanotic melanoma cells (C-32), human breast adenocarcinoma cells (MDA-MB-231), and human lung adenocarcinoma cells (A549) were selected as tested cancer lines, while cytotoxicity was investigated on normal human dermal fibroblasts (HFF-1). All the compounds were also tested against reference strains Staphylococcus aureus ATCC 29213 and Enterococcus faecalis ATCC 29212 and representatives of multidrug-resistant clinical isolates of methicillin-resistant S. aureus (MRSA) and vancomycin-resistant E. faecalis. Only the acetylene derivatives of 8-hydroxyquinoline-5-sulfonamide 3a-f were shown to be biologically active, and 8-hydroxy-N-methyl-N-(prop-2-yn-1-yl)quinoline-5-sulfonamide (3c) showed the highest activity against all three cancer lines and MRSA isolates. Its efficacies were comparable to those of cisplatin/doxorubicin and oxacillin/ciprofloxacin. In the non-cancer HFF-1 line, the compound showed no toxicity up to an IC50 of 100 μM. In additional tests, compound 3c decreased the expression of H3, increased the transcriptional activity of cell cycle regulators (P53 and P21 proteins), and altered the expression of BCL-2 and BAX genes in all cancer lines. The unsubstituted phenolic group at position 8 of the quinoline is the key structural fragment necessary for biological activity.

• MeSH
• antibakteriální látky * farmakologie   chemie   chemická syntéza   MeSH
• antitumorózní látky * farmakologie   chemie   chemická syntéza   MeSH
• chinoliny * chemie   farmakologie   chemická syntéza   MeSH
• Enterococcus faecalis účinky léků   MeSH
• lidé MeSH
• mikrobiální testy citlivosti * MeSH
• molekulární struktura MeSH
• nádorové buněčné linie MeSH
• racionální návrh léčiv MeSH
• Staphylococcus aureus účinky léků   MeSH
• sulfonamidy * farmakologie   chemie   chemická syntéza   MeSH
• vztahy mezi strukturou a aktivitou MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

The quantification of cellular metabolic activity via MTT assay has become a widespread practice in eukaryotic cell studies and is progressively extending to bacterial cell investigations. This study pioneers the application of MTT assay to evaluate the metabolic activity of biofilm-forming cells within bacterial biofilms on nanofibrous materials. The biofilm formation of Staphylococcus aureus and Escherichia coli on nanomaterials electrospun from polycaprolactone (PCL), polylactic acid (PLA), and polyamide (PA) was examined. Various parameters of the MTT assay were systematically investigated, including (i) the dissolution time of the formed formazan, (ii) the addition of glucose, and (iii) the optimal wavelength for spectrophotometric determination. Based on interim findings, a refined protocol suitable for application to nanofibrous materials was devised. We recommend 2 h of the dissolution, the application of glucose, and spectrophotometric measurement at 595 nm to obtain reliable data. Comparative analysis with the reference CFU counting protocol revealed similar trends for both tested bacteria and all tested nanomaterials. The proposed MTT protocol emerges as a suitable method for assessing the metabolic activity of bacterial biofilms on PCL, PLA, and PA nanofibrous materials.

• MeSH
• biofilmy * růst a vývoj   MeSH
• Escherichia coli * fyziologie   MeSH
• glukosa metabolismus   MeSH
• nanovlákna * chemie   MeSH
• nylony chemie   MeSH
• polyestery * chemie   MeSH
• spektrofotometrie metody   MeSH
• Staphylococcus aureus * fyziologie   MeSH
• tetrazoliové soli * metabolismus   chemie   MeSH
• thiazoly metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH

Materials used for orthopedic implants should not only have physical properties close to those of bones, durability and biocompatibility, but should also exhibit a sufficient degree of antibacterial functionality. Due to its excellent properties, titanium is still a widely used material for production of orthopedic implants, but the unmodified material exhibits poor antibacterial activity. In this work, the physicochemical characteristics, such as chemical composition, crystallinity, wettability, roughness, and release of Ti ions of the titanium surface modified with nanotubular layers were analyzed and its antibacterial activity against two biofilm-forming bacterial strains responsible for prosthetic joint infection (Staphylococcus aureus and Pseudomonas aeruginosa) was investigated. Electrochemical anodization (anodic oxidation) was used to prepare two types of nanotubular arrays with nanotubes differing in dimensions (with diameters of 73 and 118 nm and lengths of 572 and 343 nm, respectively). These two surface types showed similar chemistry, crystallinity, and surface energy. The surface with smaller nanotube diameter (TNT-73) but larger values of roughness parameters was more effective against S. aureus. For P. aeruginosa the sample with a larger nanotube diameter (TNT-118) had better antibacterial effect with proven cell lysis. Antibacterial properties of titanium nanotubular surfaces with potential in implantology, which in our previous work demonstrated a positive effect on the behavior of human gingival fibroblasts, were investigated in terms of surface parameters. The interplay between nanotube diameter and roughness appeared critical for the bacterial fate on nanotubular surfaces. The relationship of nanotube diameter, values of roughness parameters, and other surface properties to bacterial behavior is discussed in detail. The study is believed to shed more light on how nanotubular surface parameters and their interplay affect antibacterial activity.

• MeSH
• antibakteriální látky * farmakologie   chemie   MeSH
• biofilmy účinky léků   růst a vývoj   MeSH
• lidé MeSH
• mikrobiální testy citlivosti MeSH
• nanotrubičky * chemie   MeSH
• povrchové vlastnosti * MeSH
• Pseudomonas aeruginosa * účinky léků   MeSH
• Staphylococcus aureus * účinky léků   MeSH
• titan * chemie   farmakologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH