Focusing light inside live tissue using reversibly switchable bacterial phytochrome as a genetically encoded photochromic guide star.

Sci Adv

Caltech Optical Imaging Laboratory, Andrew and Peggy Cherng Department of Medical Engineering, Department of Electrical Engineering, California Institute of Technology, Pasadena, CA 91125, USA.

Published: December 2019

Focusing light deep by engineering wavefronts toward guide stars inside scattering media has potential biomedical applications in imaging, manipulation, stimulation, and therapy. However, the lack of endogenous guide stars in biological tissue hinders its translations to in vivo applications. Here, we use a reversibly switchable bacterial phytochrome protein as a genetically encoded photochromic guide star (GePGS) in living tissue to tag photons at targeted locations, achieving light focusing inside the tissue by wavefront shaping. As bacterial phytochrome-based GePGS absorbs light differently upon far-red and near-infrared illumination, a large dynamic absorption contrast can be created to tag photons inside tissue. By modulating the GePGS at a distinctive frequency, we suppressed the competition between GePGS and tissue motions and formed tight foci inside mouse tumors in vivo and acute mouse brain tissue, thus improving light delivery efficiency and specificity. Spectral multiplexing of GePGS proteins with different colors is an attractive possibility.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6905864PMC
http://dx.doi.org/10.1126/sciadv.aay1211DOI Listing

Publication Analysis

Top Keywords

focusing light
8
reversibly switchable
8
switchable bacterial
8
bacterial phytochrome
8
genetically encoded
8
encoded photochromic
8
photochromic guide
8
guide star
8
guide stars
8
tag photons
8

Similar Publications

A powerful but frequently overlooked role of thermodynamics in environmental microbiology: inspirations from anammox.

Appl Environ Microbiol

January 2025

State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, China.

Thermodynamics has long been applied in predicting undiscovered microorganisms or analyzing energy flows in microbial metabolism, as well as evaluating microbial impacts on global element distributions. However, further development and refinement in this interdisciplinary field are still needed. This work endeavors to develop a whole-cycle framework integrating thermodynamics with microbiological studies, focusing on representative nitrogen-transforming microorganisms.

View Article and Find Full Text PDF

Incorporating nanomaterials into hydrogels allows for the creation of versatile materials with properties that can be precisely tailored by manipulating their nanoscale structures, leading to a wide range of bulk properties. Investigating the structural and property characteristics of composite hydrogels is crucial in tailoring their performance for specific applications. This study focuses on investigating the correlation between the structural arrangement and properties of a composite hydrogel of thermoresponsive polymer, gelatin, and light-responsive antimicrobial porous gold nanorods (PAuNRs).

View Article and Find Full Text PDF

Objective: To investigate how surface treatment affects the color of enamel and dentin, and to evaluate whether the color differences are acceptable.

Materials And Methods: Freshly extracted premolars were prepared using diamond burs (blue, red, and yellow tapes). Tooth surfaces were divided into control and acid-etched areas and treated with phosphoric acid (5, 15, 30, 45, and 60 s).

View Article and Find Full Text PDF

Sweet cherry is a high-value crop, and strategies to enhance production and sustainability are at the forefront of research linked to this crop. The improvement of plant status is key to achieving optimum yield. Biostimulants, such as glycine betaine (GB) or seaweed-based biostimulants [e.

View Article and Find Full Text PDF

Objectives: To evaluate the effectiveness of an MRI radiomics stacking ensemble learning model, which combines T2-weighted imaging (T2WI) and contrast-enhanced T1-weighted imaging (CE-T1WI) with deep learning-based automatic segmentation, for preoperative prediction of the prognosis of high-intensity focused ultrasound (HIFU) ablation of uterine fibroids.

Methods: This retrospective study collected data from 360 patients with uterine fibroids who underwent HIFU treatment. The dataset was sourced from Center A (training set: N = 240; internal test set: N = 60) and Center B (external test set: N = 60).

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!