Nanotopography Influences Host-Pathogen Quorum Sensing and Facilitates Selection of Bioactive Metabolites in Mesenchymal Stromal Cells and Co-Cultures.

Orthopedic implant-related bacterial infections and resultant antibiotic-resistant biofilms hinder implant-tissue integration and failure. Biofilm quorum sensing (QS) communication determines the pathogen colonization success. However, it remains unclear how implant modifications and host cells are influenced by, or influence, QS.

Mechanotransducive surfaces for enhanced cell osteogenesis, a review.

Novel strategies employing mechano-transducing materials eliciting biological outcomes have recently emerged for controlling cellular behaviour. Targeted cellular responses are achieved by manipulating physical, chemical, or biochemical modification of material properties. Advances in techniques such as nanopatterning, chemical modification, biochemical molecule embedding, force-tuneable materials, and artificial extracellular matrices are helping understand cellular mechanotransduction.

Bacterial Surface Appendages Modulate the Antimicrobial Activity Induced by Nanoflake Surfaces on Titanium.

Bioinspired nanotopography is a promising approach to generate antimicrobial surfaces to combat implant-associated infection. Despite efforts to develop bactericidal 1D structures, the antibacterial capacity of 2D structures and their mechanism of action remains uncertain. Here, hydrothermal synthesis is utilized to generate two 2D nanoflake surfaces on titanium (Ti) substrates and investigate the physiological effects of nanoflakes on bacteria.

Nanotextured titanium inhibits bacterial activity and supports cell growth on 2D and 3D substrate: A co-culture study.

Medical implant-associated infections pose a significant challenge to modern medicine, with aseptic loosening and bacterial infiltration being the primary causes of implant failure. While nanostructured surfaces have demonstrated promising antibacterial properties, the translation of their efficacy from 2D to 3D substrates remains a challenge. Here, we used scalable alkaline etching to fabricate nanospike and nanonetwork topologies on 2D and laser powder-bed fusion printed 3D titanium.

Enhanced and Stem-Cell-Compatible Effects of Nature-Inspired Antimicrobial Nanotopography and Antimicrobial Peptides to Combat Implant-Associated Infection.

Nature-inspired antimicrobial surfaces and antimicrobial peptides (AMPs) have emerged as promising strategies to combat implant-associated infections. In this study, a bioinspired antimicrobial peptide was functionalized onto a nanospike (NS) surface by physical adsorption with the aim that its gradual release into the local environment would enhance inhibition of bacterial growth. Peptide adsorbed on a control flat surface exhibited different release kinetics compared to the nanotopography, but both surfaces showed excellent antibacterial properties.

Resolving physical interactions between bacteria and nanotopographies with focused ion beam scanning electron microscopy.

To robustly assess the antibacterial mechanisms of nanotopographies, it is critical to analyze the bacteria-nanotopography adhesion interface. Here, we utilize focused ion beam milling combined with scanning electron microscopy to generate three-dimensional reconstructions of or interacting with nanotopographies. For the first time, 3D morphometric analysis has been exploited to quantify the intrinsic contact area between each nanostructure and the bacterial envelope, providing an objective framework from which to derive the possible antibacterial mechanisms of synthetic nanotopographies.

Insights into complex nanopillar-bacteria interactions: Roles of nanotopography and bacterial surface proteins.

Nanopillared surfaces have emerged as a promising strategy to combat bacterial infections on medical devices. However, the mechanisms that underpin nanopillar-induced rupture of the bacterial cell membrane remain speculative. In this study, we have tested three medically relevant poly(ethylene terephthalate) (PET) nanopillared-surfaces with well-defined nanotopographies against both Gram-negative and Gram-positive bacteria.

Friction at nanopillared polymer surfaces beyond Amontons' laws: Stick-slip amplitude coefficient (SSAC) and multiparametric nanotribological properties.

Frictional and nanomechanical properties of nanostructured polymer surfaces are important to their technological and biomedical applications. In this work, poly(ethylene terephthalate) (PET) surfaces with a periodic distribution of well-defined nanopillars were fabricated through an anodization/embossing process. The apparent surface energy of the nanopillared surfaces was evaluated using the Fowkes acid-base approach, and the surface morphology was characterized using scanning electron microscope (SEM) and atomic force microscope (AFM).

Giant Cell Tumor of the Ribs and Aneurysmal Bone Cyst Presenting With Hemothorax in a Child.

Giant cell tumor (GCT) is one of the most common tumors of bone and is the most common precursor of aneurysmal bone cysts (ABC). The clinical behavior of concurrent GCT and ABC can be very aggressive in children. GCT of the ribs, with or without ABC, is rarely seen in children.