Bacterial resistance has become a global concern for public health agencies. Various resistance mechanisms found in Staphylococcus aureus strains grant this bacterium resistance to a wide range of antibiotics, contributing to the rise in human mortality worldwide. Resistance mediated by efflux pumps is one of the most prevalent mechanisms in multi-resistant bacteria, which has aroused the interest of several researchers in the search for possible efflux pump inhibitors. In view of the aforementioned considerations, it is important that new strategies, such as the synthesis of chalcones, be made available as a viable strategy in antimicrobial therapy. In this study, the synthesized chalcone (2E)-1-(3'-aminophenyl)-3-(4-dimethylaminophenyl)-prop-2-en-1-one was tested for its antibacterial activity, focusing on antibiotic modification and the inhibition of the MepA efflux pump present in S. aureus strain K2068. The broth microdilution method, using microdilution plates, was employed in microbiological tests to determine the minimum inhibitory concentration of the chalcone, antibiotics, and ethidium bromide. The results show that while the chalcone did not exhibit direct antibacterial activity, it synergistically enhanced the effects of ciprofloxacin and ethidium bromide, as evidenced by the reduction in MICs. In addition, computer simulations of molecular docking demonstrate that the tested chalcone acts on the same binding site as the efflux pump inhibitor chlorpromazine, interacting with essentially the same residues. These data suggest that the chalcone may act as a MepA inhibitor.
- MeSH
- Anti-Bacterial Agents * pharmacology chemistry chemical synthesis MeSH
- Bacterial Proteins * metabolism genetics chemistry antagonists & inhibitors MeSH
- Chalcone * pharmacology chemistry MeSH
- Chalcones * pharmacology chemistry MeSH
- Humans MeSH
- Membrane Transport Proteins * metabolism genetics chemistry MeSH
- Microbial Sensitivity Tests MeSH
- Multidrug Resistance-Associated Proteins * metabolism genetics chemistry MeSH
- Molecular Docking Simulation MeSH
- Staphylococcus aureus * drug effects genetics metabolism MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
Cíl: Úraz elektrickým proudem z vysokého napětí je jedním z nejzávažnějších úrazů, se kterými se můžeme v moderní medicíně setkat. Často bývá spojený s více následky a vysokou náchylností k infekčním komplikacím. Tito pacienti jsou přijímáni do specializovaných popáleninových center a vyžadují rozsáhlou multidisciplinární spolupráci. V této studii se snažíme odhalit prevalenci, typy a charakteristiky mikrobiálních infekcí, které se vyvíjejí po vysokonapěťovém elektrotraumatu, a identifikovat rizikové faktory, které mohou přispívat k náchylnosti pacientů k infekcím. Materiál a metodika: Pro účely této publikace byla zpracována data všech 37 pacientů hospitalizovaných na jednotce intenzivní péče Kliniky popálenin a plastické chirurgie FN Brno s diagnózou úraz elektrickým proudem vysokým napětím v letech 2006–2016. Otisky a stěry z exfoliovaných oblastí byly opakovaně odebírány k mikrobiální analýze spolu s tracheobronchiálním aspirátem, sputem nebo bronchoalveolární laváží, močí a periferní krví. Získaná data byla zpětně analyzována. Výsledky: Mezi 37 pacienty byl medián věku 31,9 s průměrnou dobou hospitalizace 44,3 dne a úmrtností 8,1 %. Na umělé plicní ventilaci bylo závislých celkem 28 osob. Výskyt infekčních komplikací se v průběhu hospitalizace liší podle místa kultivace odběru a doby strávené v nemocnici. U 97,3 % pacientů se vyvinula infekce alespoň v jednom tělesném kompartmentu. V 88,8 % případů byla multipatogenní a ve 41,6 % se rozvinul septický stav. V naší studijní kohortě dominovaly G+ nad G-kmeny. Nejčastějšími zástupci z G+ spektra byli koaguláza negativní stafylokoky (97 %), Staphylococcus aureus (57 %), Enterococcus fecalis et faecium (51 %). V G-spektru bylo pořadí následující: Klebsiella pneumoniae (46 %), Pseudomonas aeruginosa (41 %), Escherichia coli (35 %) a Acinetobacter baumannii (18,9 %). Nejčastější pozorovanou infekcí byla infekce popálenin (BWI), následovaná infekcemi krevního řečiště (BSI), infekcemi dolních cest dýchacích (LRTI) a infekcemi močových cest (UTI), primárně způsobené G+ patogeny. Je pozoruhodné, že delší doba hospitalizace byla spojena s rostoucí prevalencí G-patogenů, zejména K. pneumoniae, P. aeruginosa a A. baumannii, které vykazovaly vysoký stupeň antimikrobiální rezistence. Závěr: Tato studie poskytuje podrobný pohled na výskyt a následky úrazů elektrickým proudem s vysokým napětím na Moravě v průběhu desetiletí. Faktory významně ovlivňující přežití a závažnost výsledků zahrnovaly celkovou plochu popálenin, popáleniny v celé tloušťce, inhalační poranění a potřebu tracheostomie. Studie je však limitována relativně malou velikostí vzorku, dlouhou dobou sběru dat s potenciálními změnami v klinické praxi a jednocentrovým designem, což může ovlivnit zobecnění nálezů. K ověření těchto výsledků a zpřesnění strategií prevence infekcí u této populace pacientů jsou zapotřebí další multicentrické studie.
Background and Aim: High voltage electrotrauma is one of the most serious injuries we can encounter in modern medicine, often associated with multiple disabilities and high susceptibility to infectious complications. These patients are admitted to specialized burn centers and require extensive multidisciplinary collaboration. In this study, we aim to uncover the prevalence, types and characteristics of microbial infections that develop in the aftermath of high voltage electrotrauma and to identify risk factors that may contribute to patients’ susceptibility to infections. Material and Methods: For the purposes of this publication, data of all 37 patients hospitalized in the intensive care unit of the Department of Burns and Plastic Surgery of the University Hospital in Brno with a diagnosis of high-voltage electrical injury between 2006–2016 were processed. Imprints and swaps from exfoliated areas were repeatedly taken for microbial analysis, together with tracheobronchial aspirate fluid, sputum, or bronchoalveolar lavage, urine and peripheral blood. The obtained data were analysed retrospectively. Results: Among the 37 patients, the median age was 31.9, with an average hospital stay of 44.3 days and a mortality rate of 8.1%. A total of 28 individuals were dependent on artificial lung ventilation. The incidence of infectious complications varies during the hospitalization period according to the location of sampling cultivation and time spent at the hospital. 97.3% of patients developed infection in at least one body compartment. In 88.8% of cases, it was multipathogenic and in 41.6% a septic condition developed. In our study cohort, G+ dominated over Gstrains. Most common representatives from G+ spectrum were Coagulase negative Staphylococci (97%), Staphylococcus aureus (57%), Enterococcus fecalis et faecium (51%). In Gspectrum, the order was as followed: Klebsiella pneumoniae (46%), Pseudomonas aeruginosa (41%), Escherichia coli (35%) and Acinetobacter baumannii (18.9%). The most common infection observed was burn wound infection (BWI), followed by bloodstream infections (BSI), lower respiratory tract infections (LRTI), and urinary tract infections (UTI), primarily caused by G+ pathogens. Notably, an increased hospital stay duration was associated with a rising prevalence of Gpathogens, particularly K. pneumoniae P. aeruginosa and A. baumannii which exhibited a high degree of antimicrobial resistance. Conclusion: This study provides a detailed insight into the occurrence and consequences of high-voltage electrical injuries in Moravia over a decade. Factors significantly impacting survival and severity of outcomes included total burn surface area, full-thickness burns, inhalation injury, and the need for tracheostomy. However, the study is limited by its relatively small sample size, long data collection period with potential changes in clinical practice, and single-center design, which may affect the generalizability of the findings. Further multicentric studies are needed to validate these results and refine infection prevention strategies in this patient population.
- MeSH
- Cross Infection MeSH
- Wound Infection * microbiology MeSH
- Intensive Care Units MeSH
- Klebsiella pneumoniae pathogenicity MeSH
- Humans MeSH
- Microbiological Techniques methods MeSH
- Burns, Electric * microbiology MeSH
- Burns * microbiology MeSH
- Pseudomonas aeruginosa pathogenicity MeSH
- Staphylococcus aureus pathogenicity MeSH
- Population Surveillance MeSH
- Check Tag
- Humans MeSH
Cíl: Používání filtroventrilačních systémů v městských autobusech ve vyspělých zemích zvyšuje komfort a kvalitu vnitřního ovzduší v prostředcích pozemní dopravy. Mikrobiální kontaminace byla studována na výstupních a vstupních plochách 5 vzduchových filtrů vyjmutých z klimatizačního systému městských autobusů při pravidelné údržbě. Materiál a metodika: K získání vzorků z výstupní i vstupní strany filtrů byla použita technika suchého stěru. Kultivace byla provedena na různých selektivních nebo selektivně-diagnostických půdách pro kultivaci životaschopných bakterií. K identifikaci bakteriálních druhů bylo použito barvení podle Grama a imerzní mikroskopie. Vybrané kolonie byly rovněž podrobeny proteomické studii. Po identifikaci byly bakterie kvantifikovány. Výsledky: Na vstupním i výstupním povrchu filtrů převažovaly bakterie rodu Bacillus – Bacillus cereus, Bacillus subtilis, Bacillus licheniformis, Bacillus pumilus, Bacillus flexus. Identifikovány byli také bakterie rodů Staphylococcus, Brevibacillus, Peribacillus a Paenibacillus. Kvantifikace ukázala nízkou kontaminaci výstupních povrchů filtrů 1 a 2. Kontaminace vstupní a výstupní strany filtrů 3, 4 a 5 a odhalila téměř stejnou kontaminaci vstupních a výstupních ploch. Závěry: Podle nalezených výsledků doporučujeme buď častější výměnu filtrů, nebo volbu filtrů s nižší porozitou.
The use of HVAC in urban buses in developed countries increases the comfort and indoor air quality in the means of ground transportation. The microbial contamination was studied on outlet and inlet surfaces of 5 air filters removed from the urban buses HVAC during regular maintenance. To acquire samples from both the outlet and the inlet sides of the filters, dry swabbing technique was used. Cultivation was performed on different selective or selective-diagnostic agars, to cultivate viable bacteria. To identify the bacterial species, Gram stain and immerse microscopy was used. Selected colonies underwent the proteomic study (MALDI-TOF) as well. After identification, bacteria were quantified. The bacteria of the genus Bacillus – Bacillus cereus, Bacillus subtilis, Bacillus licheniformis, Bacillus pumilus, Bacillus flexus prevailed on both inlet and outlet surfaces of the filters. The members of genera Staphylococcus, Brevibacillus, Peribacillus or Paenibacillus were also identified. The quantification of colony forming units showed low contamination of the outlet surfaces of filters 1 and 2. The contamination of inlet and outlet sides of filters 3, 4, and 5 was comparable, revealed nearly the same contamination of inlet and outlet surfaces. In the case of filters 3, 4 and 5 we recommend more frequent filter changing or more efficient filter choice.
Cíl: Cílem studie bylo zmapovat výskyt bakterií Staphylococcus aureus a meticilin-rezistentních Staphylococcus aureus v prostředí univerzitního kampusu. Důraz byl kladen na identifikaci potenciálně rizikových míst z hlediska častého kontaktu s povrchy a vysoké koncentrace osob. Metody: Vzorkování probíhalo na předem vytipovaných lokalitách univerzity za použití sterilních stěrových houbiček. Odebraný materiál byl pomnožen v pufrované peptonové vodě (24 hod, 37 °C) a dále kultivován na selektivních médiích. Výskyt bakterií Staphylococcus aureus a meticilin-rezistentních Staphylococcus aureus byl potvrzen pomocí metody PCR. U izolátů meticilin-rezistentních S. aureus byly dále detekovány geny virulence, určeny spa typy a testována rezistence k antimikrobikům. Výsledky: Celkem bylo analyzováno 312 vzorků odebraných z povrchů v univerzitních koridorech, knihovně a dvou stravovacích zařízeních. S. aureus byl detekován ve 210 vzorcích (67,3 %). Získáno bylo také 8 izolátů meticilin-rezistentních S. aureus (2,6 %). Identifikovány byly spa typy meticilin-rezistentních S. aureus t304 (častý na Blízkém východě) a t011 náležející ke klonální linii ST398, t126 a t189. Tři izoláty meticilin-rezistentních S. aureus byly klasifikovány jako multirezistentní. Závěr: Výsledky poukazují na významnou kontaminaci univerzitního prostředí bakteriemi Staphylococcus aureus a meticilin- rezistentních Staphylococcus aureus, zejména na površích s vysokou frekvencí dotyku. Zdůrazňuje se potřeba časté a cílené dezinfekce, vhodné volby čisticích prostředků a důsledné podpory hygieny rukou mezi studenty i zaměstnanci. Monitoring těchto patogenů může být klíčovým nástrojem prevence komunitního šíření, a to i s ohledem na možný přenos do zdravotnických zařízení.
Objective: The aim of this study was to assess the occurrence of Staphylococcus aureus (SA) and methicillin-resistant S. aureus (MRSA) in a university campus environment. Emphasis was placed on identifying potentially high-risk areas with frequent surface contact and high population density. Methods: Sampling was conducted at pre-selected locations across the university using sterile swab sponges. Samples were enriched in buffered peptone water (24 h, 37 °C) and subsequently cultured on selective media. The presence of SA/MRSA was confirmed using PCR. For MRSA isolates, virulence genes were detected, spa types were determined, and antimicrobial resistance was tested. Results: A total of 312 surface samples were collected from university corridors, the library, and two dining facilities. S. aureus was detected in 210 samples (67.3%). Additionally, 8 MRSA isolates were obtained (2.6%). Identified MRSA spa types included t304 (common in the Middle East), t011 belonging to the clonal lineage ST398, as well as t126 and t189. Three MRSA isolates were classified as multidrug-resistant. Conclusion: The findings highlight significant contamination of the university environment with SA and MRSA, particularly on frequently touched surfaces. The results underscore the importance of regular and targeted disinfection, appropriate selection of cleaning agents, and consistent promotion of hand hygiene among students and staff. Monitoring these pathogens may be a key tool in preventing community spread, especially considering the potential for transmission into healthcare settings.
- Keywords
- kontaminace povrchů,
- MeSH
- Fomites microbiology MeSH
- Humans MeSH
- Methicillin-Resistant Staphylococcus aureus * isolation & purification MeSH
- Staphylococcus aureus * isolation & purification MeSH
- Universities * MeSH
- Environmental Exposure MeSH
- Check Tag
- Humans MeSH
- Publication type
- Research Support, Non-U.S. Gov't MeSH
Current antibiotics and chemotherapeutics are becoming ineffective because pathogenic bacteria and tumor cells have developed multiple drug resistance. Therefore, it is necessary to find new substances that can be used in treatment, either alone or as sensitizing molecules in combination with existing drugs. Peptaibols are bioactive, membrane-active peptides of non-ribosomal origin, mainly produced by filamentous fungi such as Trichoderma spp. This study focused on producing peptaibol-rich extracts from Trichoderma atroviride O1, cultivated on malt extract agar (MA) under circadian and constant darkness conditions for 13 days. Peptaibol production was detected by MALDI-TOF mass spectrometry after six days of cultivation. The extracts demonstrated antibacterial activity against Staphylococcus aureus strains, particularly the methicillin-resistant variant, but not against the Gram-negative Pseudomonas aeruginosa. Quorum sensing interference revealed that a peptaibol-rich extract suppressed Vibrio campbellii BAA-1119's AI-2 signaling system to a degree comparable with gentamycin. Beyond antibacterial properties, the extracts exhibited notable antiproliferative activity against human ovarian cancer cells and their adriamycin-resistant subline in both 2D and 3D models. Specifically, MA-derived extracts reduced ovarian cancer cell viability by 70% at 50 μg/mL, especially under light/dark regime of cultivation. Compared to previously published results for PDA-based extracts, MA cultivation shifted the biological effects of peptaibol-containing extracts toward anticancer potential. These findings support the idea that modifying fungal cultivation parameters, the bioactivity of secondary metabolite mixtures can be tailored for specific therapeutic applications.
- MeSH
- Agar * chemistry MeSH
- Anti-Bacterial Agents * pharmacology metabolism MeSH
- Hypocreales MeSH
- Culture Media chemistry MeSH
- Humans MeSH
- Microbial Sensitivity Tests MeSH
- Cell Line, Tumor MeSH
- Peptaibols * pharmacology metabolism biosynthesis chemistry MeSH
- Cell Proliferation drug effects MeSH
- Antineoplastic Agents * pharmacology metabolism MeSH
- Pseudomonas aeruginosa drug effects MeSH
- Staphylococcus aureus drug effects MeSH
- Trichoderma * metabolism growth & development chemistry MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
Azo dyes are used as coloring agent in textile industries at larger scale. As a result, large quantity of dye-enriched waste water is generated which subsequently poses environmental problems. Biological tool involving bacteria having azoreductase enzyme has proved to be more effective and efficient in dye effluent treatment. Current work focuses on Staphylococcus caprae (S. caprae) for degradation and decolorization of Reactive Red-195 (RR-195) azo dye. For this purpose, factors such as pH, temperature, inoculums, carbon and nitrogen sources, and dye concentrations have been optimized for maximum decolorization and degradation. S. caprae (4 mg/mL) efficiently resulted into 90% decolorization of RR-195 dye under static condition at 100 μg/mL concentration, 30 °C and pH 7.0 at a 12-h contact period. FTIR analysis has revealed the formation of new functional groups in the treated dye such as O-H stretch at 3370 cm-1, C-H band stretching at 2928 cm-1, and new band at 1608 cm-1 which specify the degradation of aromatic ring, 1382 and 1118 cm-1 represents desulfonated peaks. Biodegraded metabolites of RR-195 dye such as phenol, 3, 5-di-tert-butylphenol, and phthalic acid have been identified respectively that find industrial applications. Phytotoxicity test has shown non-toxic effects of treated dye on germination of Vigna radiata and Triticum aestivum seeds. Further, antibiotic diffusion assay has confirmed the biosafety of S. caprae.
- MeSH
- Azo Compounds * metabolism toxicity MeSH
- Coloring Agents * metabolism MeSH
- Biodegradation, Environmental * MeSH
- Water Pollutants, Chemical metabolism MeSH
- Nitrogen metabolism MeSH
- Hydrogen-Ion Concentration MeSH
- Wastewater * microbiology chemistry MeSH
- Industrial Waste MeSH
- Staphylococcus capitis metabolism isolation & purification MeSH
- Staphylococcus metabolism MeSH
- Temperature MeSH
- Textiles MeSH
- Textile Industry MeSH
- Carbon metabolism MeSH
- Publication type
- Journal Article MeSH
Antibiotic resistance is one of the biggest threats to global health. Fungal endophytes are important sources of active natural products with antimicrobial potential. The purpose of this study was to characterize the endophytes coexisting with Helichrysum oocephalum, evaluate their antimicrobial activities, and annotate the endophytes metabolites. Six fungal species, including Fusarium avenaceum and Fusarium tricinctum, were identified. Endophytes were cultured, and their metabolites were extracted. The antimicrobial effects of the extracts were tested against Staphylococcus aureus, Bacillus cereus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans. In addition, anti-biofilm effects of the extracts were examined against P. aeruginosa and S. epidermidis. The metabolites in the most active extract were annotated on the basis of the LC-ESI-QToF-MS/MS data. In anti-biofilm studies, F. avenaceum extract was effective in destroying and inhibiting the biofilm formation of S. epidermidis. LC-MS analysis showed that most of the identified compounds in the active extracts were enniatins (cyclic hexadepsipeptides). However, apicidin derivatives were also annotated. Our results revealed that these endophytes, especially Fusarium species, have antimicrobial activity against S. aureus, B. cereus, and C. albicans and anti-biofilm activity against S. epidermidis. According to the literature, the observed antimicrobial activity can be attributed to the enniatins. However, further phytochemical and pharmacological studies are necessary in this regard.
- MeSH
- Anti-Bacterial Agents * pharmacology isolation & purification chemistry MeSH
- Antifungal Agents * pharmacology isolation & purification chemistry MeSH
- Anti-Infective Agents * pharmacology isolation & purification chemistry MeSH
- Bacillus cereus drug effects MeSH
- Biofilms drug effects MeSH
- Candida albicans drug effects MeSH
- Endophytes * chemistry metabolism isolation & purification MeSH
- Escherichia coli drug effects MeSH
- Fusarium * chemistry metabolism MeSH
- Microbial Sensitivity Tests MeSH
- Pseudomonas aeruginosa drug effects MeSH
- Staphylococcus aureus drug effects MeSH
- Staphylococcus epidermidis drug effects MeSH
- Tandem Mass Spectrometry MeSH
- Publication type
- Journal Article MeSH
BACKGROUND: Antimicrobial lock therapy is recommended for preventing and treating catheter-related bloodstream infections, but different solutions have uncertain efficacy. METHODS: Two locks, 1.35% taurolidine and 4% ethylenediaminetetraacetic acid (EDTA), were tested on Staphylococcus epidermidis, Staphylococcus aureus, methicillin-resistant S. aureus, Pseudomonas aeruginosa, multidrug-resistant P. aeruginosa, vancomycin-resistant Enterococcus faecium, Klebsiella oxytoca (carbapenemase producing), K. pneumoniae (extended-spectrum β-lactamase producing), Candida albicans, and Candida glabrata. Broviac catheter segments were incubated with these organisms and then exposed to various lock solutions. Colony-forming units (CFUs) were counted after 2, 4, and 24 h of incubation. RESULTS: Taurolidine showed a significant decrease in CFUs after 2 h in S. aureus, S. epidermidis, methicillin-resistant S. aureus, vancomycin-resistant E. faecium, P. aeruginosa (both sensitive and multidrug-resistant strains), K. oxytoca, C. albicans, and C. glabrata. After 4 h, significant reductions were noted in S. aureus, S. epidermidis, methicillin-resistant S. aureus, P. aeruginosa, multidrug-resistant P. aeruginosa, K. pneumoniae, K. oxytoca, and C. albicans. Taurolidine was also effective after 24 h, especially against methicillin-resistant S. aureus and multidrug-resistant P. aeruginosa. Four percent EDTA acid showed a significant reduction in CFUs after 2 h in S. aureus, vancomycin-resistant E. faecium, P. aeruginosa, K. oxytoca, C. albicans, and C. glabrata. After 4 h, reductions occurred in P. aeruginosa, multidrug-resistant P. aeruginosa, K. oxytoca, and C. albicans and after 24 h in methicillin-resistant S. aureus, P. aeruginosa, and K. oxytoca. CONCLUSION: Taurolidine is more effective than 4% EDTA acid in eradicating Gram-positive and Gram-negative microorganisms and fungi.
- MeSH
- Anti-Infective Agents * pharmacology MeSH
- Candida albicans drug effects MeSH
- Edetic Acid * pharmacology MeSH
- Catheter-Related Infections * prevention & control microbiology MeSH
- Humans MeSH
- Methicillin-Resistant Staphylococcus aureus drug effects MeSH
- Microbial Sensitivity Tests MeSH
- Colony Count, Microbial MeSH
- Pseudomonas aeruginosa drug effects MeSH
- Staphylococcus aureus drug effects MeSH
- Staphylococcus epidermidis drug effects MeSH
- Taurine * analogs & derivatives pharmacology MeSH
- Thiadiazines * pharmacology MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Comparative Study MeSH
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
- Bacterial Toxins * biosynthesis genetics MeSH
- History, 21st Century MeSH
- Adult MeSH
- Exotoxins * genetics biosynthesis MeSH
- Leukocidins * genetics MeSH
- Humans MeSH
- Methicillin-Resistant Staphylococcus aureus * genetics isolation & purification MeSH
- Staphylococcal Infections * microbiology epidemiology MeSH
- Check Tag
- History, 21st Century MeSH
- Adult MeSH
- Humans MeSH
- Male MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Historical Article MeSH
- Geographicals
- Czech Republic MeSH
