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Tissue development requires local and long-distance communication between cells. Cell ablation experiments have provided critical insights into the functions of specific cell types and the tissue surrounding the dead cells. In theDrosophilaneuromuscular system, ablation of motor neurons and muscles has revealed the roles of the ablated cells in axon pathfinding and circuit wiring. For example, when muscles are denervated due to laser ablation of their motor neuron inputs, they receive ectopic innervation from neighboring motor neurons. Here, we describe two methods of specific cell ablation. The first is a genetic ablation approach that usesGAL4(ideally expressed in a small subset of cells) to drive expression of cell death genesreaperandhead involution defective. The second method relies on reactive oxygen species produced by light activation of theArabidopsis-derived Singlet Oxygen Generator, miniSOG2, expressed in a subset of cells. For the latter, the precision stems from both theGAL4and the restricting of the blue-light stimulation area.
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This content will become publicly available on March 29, 2025
Photoacoustic image guidance for laser tonsil ablation: approach and initial results
Tonsillectomy, one of the most common surgical procedures worldwide, is often associated with postoperative complications, particularly bleeding. Tonsil laser ablation has been proposed as a safer alternative; however, its adoption has been limited because it can be difficult for a surgeon to visually control the thermal interactions that occur between the laser and the tissue. In this study, we propose to monitor the ablation caused by a CO2 laser on ex-vivo tonsil tissue using photoacoustic imaging. Soft tissue’s unique photoacoustic spectra were used to distinguish between ablated and non-ablated tissue. Our results suggest that photoacoustic imaging is able to visualize necrosis formation and calculate the necrotic extent, offering the potential for improved tonsil laser ablation outcomes.
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- Award ID(s):
- 2237011
- PAR ID:
- 10520321
- Editor(s):
- Rettmann, Maryam E; Siewerdsen, Jeffrey H
- Publisher / Repository:
- SPIE
- Date Published:
- ISBN:
- 9781510671607
- Page Range / eLocation ID:
- 44
- Format(s):
- Medium: X
- Location:
- San Diego, United States
- Sponsoring Org:
- National Science Foundation
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