The aim of this investigation was to determine whether the antioxidant defences protect resistant strains of Staphylococcus aureus against ciprofloxacin oxidative damage. Reactive oxygen species (ROS) were determined by chemiluminescence and nitric oxide (NO) was assayed by Griess reaction. The accumulation of ciprofloxacin was examined by fluorometry and oxidation of protein, catalase, ferrous reduction antioxidant potency (FRAP), carbonyls and advanced oxidation protein products (AOPP), studied by spectrophotometry. Ciprofloxacin stimulated higher production of ROS and NO in the susceptible strains than in the resistant ones. There was higher accumulation of antibiotic in sensitive strains than in resistant ones, except for the most resistant strain, which accumulated an elevated amount of antibiotic. The FRAP/ciprofloxacin accumulation ratio of the antibiotic was lower in sensitive than in resistant strains. The most resistant strain exhibited the highest FRAP and presented a high catalase activity. There was oxidation of proteins in the presence of ciprofloxacin, with the carbonyl residues increasing in sensitive and resistant S. aureus. The degradation of carbonyls to AOPP in oxidized proteins was higher in the resistant than in sensitive strains. In conclusion, an increase in antioxidant capacity and a rapid oxidation of carbonyls to AOPP contributed to resistance to ciprofloxacin.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1111/j.1472-8206.2009.00806.x | DOI Listing |
Sci Rep
January 2025
College of Geosciences and Engineering, North China University of Water Resources and Electric Power, Zhengzhou, 450046, China.
The failure of locked-segment landslides is associated with the destruction of locked segments that exhibit an energy accumulation effect. Thus, understanding their failure mode and instability mechanism for landslide hazard prevention and control is critical. In this paper, multiple instruments, such as tilt sensors, pore water pressure gauges, moisture sensors, matrix suction sensors, resistance strain gauges, miniature earth pressure sensors, a three-dimensional (3D) laser scanner, and a camera, were used to conduct the physical model tests on the rainfall-induced arch locked-segment landslide to analyze the resulting tilting deformation and evolution mechanism.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Biochemistry, Faculty of Science, Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic.
Antibiotic-resistant strains of Staphylococcus aureus pose a significant threat in healthcare, demanding urgent therapeutic solutions. Combining bacteriophages with conventional antibiotics, an innovative approach termed phage-antibiotic synergy, presents a promising treatment avenue. However, to enable new treatment strategies, there is a pressing need for methods to assess their efficacy reliably and rapidly.
View Article and Find Full Text PDFJ Appl Microbiol
January 2025
College of Life Sciences, Nanjing Normal University, Nanjing 210023, China.
Aim: This study was dedicated to investigating the role of sulfur metabolic processes in sulfate-reducing bacteria in plant resistance to heavy metal contamination.
Methods And Results: We constructed sulfate-reducing bacterial communities based on the functional properties of sulfate-reducing strains, and then screened out the most effective sulfate-reducing bacterial community SYN1, that prevented Cd and Pb uptake in rice through hydroponic experiment. This community lowered Cd levels in the roots and upper roots by 36.
J Infect
January 2025
National Key Laboratory of Agricultural Microbiology, College of Fisheries, Huazhong Agricultural University, Wuhan, PR China; Hubei Hongshan Laboratory, Wuhan, PR China; Engineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt, Ministry of Education, Wuhan, PR China. Electronic address:
Objectives: Emerging human pathogens of animal origin have become an increasing public health concern in recent years. The aim of this study was to investigate the transmission of group B streptococcus (GBS) clonal complex (CC) 61 strains in the southern Chinese population and analyze their genetic characteristics.
Methods: Whole-genome sequencing was performed on 693 clinical isolates of GBS collected from southern China between 2016 and 2021, and the prevalence of human CC61 isolates was investigated by genomic epidemiology.
Infect Dis Now
January 2025
Department of Global Health and Development, London School of Hygiene and Tropical Medicine, UK.
Antimicrobial resistance (AMR) poses a global health challenge, particularly in maritime environments where unique conditions foster its emergence and spread. Characterized by confined spaces, high population density, and extensive global mobility, ships create a setting ripe for the development and dissemination of resistant pathogens. This review aims to analyse the contributing factors, epidemiological challenges, mitigation strategies specific to AMR on ships and to propose future research directions, bridging a significant gap in the literature.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!