Weibao Qiu

Bio: Weibao Qiu is an academic researcher from Chinese Academy of Sciences. The author has contributed to research in topics: Ultrasonic sensor & Imaging phantom. The author has an hindex of 17, co-authored 100 publications receiving 1153 citations. Previous affiliations of Weibao Qiu include University of Glasgow.

Ultrasonic Control of Neural Activity through Activation of the Mechanosensitive Channel MscL

Abstract: Externally controlling the excitation of a neuronal subset through ion channels activation can modulate the firing pattern of an entire neural circuit in vivo. As nanovalves in the cell membrane, ion channels can be opened by light (optogenetics) or ultrasonic (sonogenetics) means. A thoroughly analyzed force sensor is the Escherichia coli mechanosensitive channel of large conductance (MscL). Here we expressed MscL in rat hippocampal neurons in a primary culture and showed that it could be activated by low-pressure ultrasound pulses. The gain-of-function mutation, I92L, sensitized MscL’s sonic response, triggering action potentials at a peak negative pressure as low as 0.25 MPa. Further, the I92L MscL reliably elicited individual spikes by timed brief pulses, making excitation programmable. Because MscL opens to tension in the lipid bilayer, requiring no other proteins or ligands, it could be developed into a general noninvasive sonogenetic tool to manipulate the activities of neurons or other cells and p...

Monitoring the Opening and Recovery of the Blood–Brain Barrier with Noninvasive Molecular Imaging by Biodegradable Ultrasmall Cu2–xSe Nanoparticles

Abstract: The reversible and controllable opening and recovery of the blood–brain barrier (BBB) is crucial for the treatment of brain diseases, and it is a big challenge to noninvasively monitor these processes. In this article, dual-modal photoacoustic imaging and single-photon-emission computed tomography imaging based on ultrasmall Cu2–xSe nanoparticles (3.0 nm) were used to noninvasively monitor the opening and recovery of the BBB induced by focused ultrasound in living mice. The ultrasmall Cu2–xSe nanoparticles were modified with poly(ethylene glycol) to exhibit a long blood circulation time. Both small size and long blood circulation time enable them to efficiently penetrate into the brain with the assistance of ultrasound, which resulted in a strong signal at the sonicated site and allowed for photoacoustic and single-photon emission computed tomography imaging monitoring the recovery of the opened BBB. The results of biodistribution, blood routine examination, and histological staining indicate that the acc...

Improved Anatomical Specificity of Non-invasive Neuro-stimulation by High Frequency (5 MHz) Ultrasound

Abstract: Low frequency ultrasound (<1 MHz) has been demonstrated to be a promising approach for non-invasive neuro-stimulation. However, the focal width is limited to be half centimeter scale. Minimizing the stimulation region with higher frequency ultrasound will provide a great opportunity to expand its application. This study first time examines the feasibility of using high frequency (5 MHz) ultrasound to achieve neuro-stimulation in brain and verifies the anatomical specificity of neuro-stimulation in vivo. 1 MHz and 5 MHz ultrasound stimulation were evaluated in the same group of mice. Electromyography (EMG) collected from tail muscles together with the motion response videos were analyzed for evaluating the stimulation effects. Our results indicate that 5 MHz ultrasound can successfully achieve neuro-stimulation. The equivalent diameter (ED) of the stimulation region with 5 MHz ultrasound (0.29 ± 0.08 mm) is significantly smaller than that with 1 MHz (0.83 ± 0.11 mm). The response latency of 5 MHz ultrasound (45 ± 31 ms) is also shorter than that of 1 MHz ultrasound (208 ± 111 ms). Consequently, high frequency (5 MHz) ultrasound can successfully activate the brain circuits in mice. It provides a smaller stimulation region, which offers improved anatomical specificity for neuro-stimulation in a non-invasive manner.

Monitoring of the central blood pressure waveform via a conformal ultrasonic device.

Abstract: Continuous monitoring of the central-blood-pressure waveform from deeply embedded vessels, such as the carotid artery and jugular vein, has clinical value for the prediction of all-cause cardiovascular mortality. However, existing non-invasive approaches, including photoplethysmography and tonometry, only enable access to the superficial peripheral vasculature. Although current ultrasonic technologies allow non-invasive deep-tissue observation, unstable coupling with the tissue surface resulting from the bulkiness and rigidity of conventional ultrasound probes introduces usability constraints. Here, we describe the design and operation of an ultrasonic device that is conformal to the skin and capable of capturing blood-pressure waveforms at deeply embedded arterial and venous sites. The wearable device is ultrathin (240 μm) and stretchable (with strains up to 60%), and enables the non-invasive, continuous and accurate monitoring of cardiovascular events from multiple body locations, which should facilitate its use in a variety of clinical environments.