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Silicone elastomer medical implants are ubiquitous in medicine, particularly for breast augmentation. However, when these devices are placed within the body, disruption of the natural biological interfaces occurs, which significantly changes the native energy-dissipation mechanisms of living systems. These new interfaces can introduce non-physiological contact pressures and tribological conditions that provoke inflammation and soft tissue damage. Despite their significance, the biotribological properties of implant-tissue and implant-extracellular matrix (ECM) interfaces remain poorly understood. Here, we developed an in vitro model of soft tissue damage using a custom-built in situ biotribometer mounted onto a confocal microscope. Sections of commercially-available silicone breast implants with distinct and clinically relevant surface roughness ([Formula: see text]m, [Formula: see text]m, and [Formula: see text]m) were mounted to spherically-capped hydrogel probes and slid against collagen-coated hydrogel surfaces as well as healthy breast epithelial (MCF10A) cell monolayers to model implant-ECM and implant-tissue interfaces. In contrast to the “smooth” silicone implants ([Formula: see text]m), we demonstrate that the “microtextured” silicone implant ([Formula: see text]m) induced higher frictional shear stress ([Formula: see text] Pa), which led to greater collagen removal and cell rupture/delamination. Our studies may provide insights into post-implantation tribological interactions between silicone breast implants and soft tissues.
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This content will become publicly available on September 1, 2026
A modular, adaptable, and accessible implant kit for chronic electrophysiological recordings in rats
Electrophysiological implants enable exploration of the relationship between neuronal activity and behavior. These technologies evolve rapidly, with multiple iterations of recording systems developed and utilized. Chronic implants must address a litany of complications, including retention of high signal-to-noise ratio in probes and the ability to withstand excess force over the experimental period. To overcome these issues, we designed a chronic implant for rats. Our comprehensive protocol optimizes the entire implant process, from assembling and testing the probes (Neuropixels) to implantation. In addition to addressing the complications previously mentioned, our implant can vertically adjust probes with micron precision and is con- structed using modular components, allowing it to be easily modified for various research contexts, electro- physiological recording systems, headstages, and probe types.
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- Award ID(s):
- 2235858
- PAR ID:
- 10658300
- Publisher / Repository:
- Cell Report Methods
- Date Published:
- Journal Name:
- Cell Reports Methods
- Volume:
- 5
- Issue:
- 9
- ISSN:
- 2667-2375
- Page Range / eLocation ID:
- 101146
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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