Proc Natl Acad Sci U S A
October 2024
Although free radicals, which are generated by macrophages play a key role in antimicrobial activities, macrophages sometimes fail to kill () as bacteria have evolved mechanisms to withstand oxidative stress. In the past decades, several ROS-related staphylococcal proteins and enzymes were characterized to explain the microorganism's antioxidative defense system. Yet, time-resolved and site-specific free radical/ROS detection in bacterial infection were full of challenges.
View Article and Find Full Text PDFAntimicrob Steward Healthc Epidemiol
September 2022
Objective: Duodenoscopy-associated infections and outbreaks are reported globally despite strict adherence to duodenoscope reprocessing protocols. Therefore, new developments in the reprocessing procedure are needed.
Design: We evaluated a novel dynamic flow model for an additional cleaning step between precleaning and manual cleaning in the reprocessing procedure.
Acetaminophen overdoses cause cell injury in the liver. It is widely accepted that liver toxicity is initiated by the reactive -acetyl--aminophenol (APAP) metabolite -acetyl--benzoquinone imine (NAPQI), which first depletes glutathione and then irreversibly binds to mitochondrial proteins and nuclear DNA. As a consequence, mitochondrial respiration is inhibited, and DNA strands break.
View Article and Find Full Text PDFAntimicrobials with nonselective antibacterial efficacy such as chlorhexidine can be effective in reducing biofilm, but bear the risk of inducing resistance in specific bacteria. In clinical practice, bacteria such as have been found resistant to chlorhexidine, but other bacteria, including , have largely remained susceptible to chlorhexidine despite its widespread use in oral healthcare. Here, we aim to forward a possible reason as to why can acquire resistance against chlorhexidine, while remains susceptible to chlorhexidine.
View Article and Find Full Text PDFPreventing bacterial infections from becoming the leading cause of death by the year 2050 requires the development of novel, infection-control strategies, building heavily on biomaterials science, including nanotechnology. Pre-clinical (animal) studies are indispensable for this development. Often, animal infection outcomes bear little relation to human clinical outcome.
View Article and Find Full Text PDFOptical-coherence-tomography (OCT) is a non-destructive tool for biofilm imaging, not requiring staining, and used to measure biofilm thickness and putative comparison of biofilm structure based on signal intensity distributions in OCT-images. Quantitative comparison of biofilm signal intensities in OCT-images, is difficult due to the auto-scaling applied in OCT-instruments to ensure optimal quality of individual images. Here, we developed a method to eliminate the influence of auto-scaling in order to allow quantitative comparison of biofilm densities in different images.
View Article and Find Full Text PDFMultidrug resistant bacterial infections threaten to become the number one cause of death by the year 2050. Development of antimicrobial dendritic polymers is considered promising as an alternative infection control strategy. For antimicrobial dendritic polymers to effectively kill bacteria residing in infectious biofilms, they have to penetrate and accumulate deep into biofilms.
View Article and Find Full Text PDFAntimicrob Agents Chemother
April 2019
colonizes the sputum of most adult cystic fibrosis patients, forming difficult-to-eradicate biofilms in which bacteria are protected in their self-produced extracellular polymeric substance (EPS) matrices. EPS provide biofilms with viscoelastic properties, causing time-dependent relaxation after stress-induced deformation, according to multiple characteristic time constants. These time constants reflect different biofilm (matrix) components.
View Article and Find Full Text PDFNosocomial infections are a major problem in medical health care. To solve this problem, a series of antimicrobial waterborne paints were prepared by using antimicrobial hyperbranched (HB) emulsifiers. The HB-emulsifiers were prepared by polymerizing AB monomers obtained in a one-step reaction of bis(hexamethylene)triamine and carbonyl biscaprolactam.
View Article and Find Full Text PDFIn real-life situations, bacteria are often transmitted from biofilms growing on donor surfaces to receiver ones. Bacterial transmission is more complex than adhesion, involving bacterial detachment from donor and subsequent adhesion to receiver surfaces. Here, we describe a new device to study shear-induced bacterial transmission from a (stainless steel) pipe to a (silicone rubber) tube and compare transmission of EPS-producing and non-EPS-producing staphylococci.
View Article and Find Full Text PDFBackground: Three European centers have recently reported dramatic failures of the STRATOS titanium system, approved in Europe and the United States since 2007 and meant for pectus repair, without detailed exploration of its causes.
Methods: Failed implants (fractures or loosened crimp connectors) were surgically explanted from 12 patients and biopsies taken from surrounding discolored tissue. Detailed failure analysis was performed to find the cause of failures.
An important limitation in cell therapy for the regeneration of tissue is the initial lack of oxygen. After implantation of large 3D cell-seeded structures, cells die rather than contribute to tissue regenerating. Here we've tested oxygen-releasing materials to improve cell survival and growth after implantation.
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