Journal ArticleDOI
Direct observations of ultrasound microbubble contrast agent interaction with the microvessel wall
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The oscillation of these microbubbles in small vessels is directly observed and shown to be substantially different than that predicted by previous models and imaged within large fluid volumes.Abstract:
Many thousands of contrast ultrasound studies have been conducted in clinics around the world. In addition, the microbubbles employed in these examinations are being widely investigated to deliver drugs and genes. Here, for the first time, the oscillation of these microbubbles in small vessels is directly observed and shown to be substantially different than that predicted by previous models and imaged within large fluid volumes. Using pulsed ultrasound with a center frequency of 1 MHz and peak rarefactional pressure of 0.8 or 2.0 MPa , microbubble expansion was significantly reduced when microbubbles were constrained within small vessels in the rat cecum ( p < 0.05 ) . A model for microbubble oscillation within compliant vessels is presented that accurately predicts oscillation and vessel displacement within small vessels. As a result of the decreased oscillation in small vessels, a large resting microbubble diameter resulting from agent fusion or a high mechanical index was required to bring the agent shell into contact with the endothelium. Also, contact with the endothelium was observed during asymmetrical collapse, not during expansion. These results will be used to improve the design of drug delivery techniques using microbubbles.read more
Citations
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Controlled and targeted tumor chemotherapy by ultrasound-activated nanoemulsions/microbubbles.
TL;DR: No therapeutic effect from the nanodroplet/ultrasound combination was observed without the drug, indicating that therapeutic effect was caused by the ultrasound-enhanced chemotherapeutic action of the tumor-targeted drug, rather than the mechanical or thermal action of ultrasound itself.
Journal ArticleDOI
The dynamics of the piezo inkjet printhead operation
TL;DR: In this paper, the physics behind the two-way coupling from the electrical to the mechanical domain through the piezoelectric actuator, where an electrical signal is transformed into a mechanical deformation of the printhead structure, is discussed.
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Scanning ultrasound removes amyloid-β and restores memory in an Alzheimer’s disease mouse model
Gerhard Leinenga,Jürgen Götz +1 more
TL;DR: Repeated scanning ultrasound treatments of the mouse brain to remove Aβ, without the need for any additional therapeutic agent such as anti-Aβ antibody, are used and suggest that repeated SUS may be a noninvasive method with potential for treating Alzheimer’s disease.
Journal ArticleDOI
Ultrasound contrast microbubbles in imaging and therapy: physical principles and engineering
TL;DR: A review of the physical aspects of these agents, exploring microbubble imaging modes, models for micro bubble oscillation and the interaction of the micro bubble with the endothelium can be found in this article.
Journal ArticleDOI
Acoustic behavior of microbubbles and implications for drug delivery
TL;DR: Phenomena relevant to drug delivery, such as non-spherical oscillations, shear stress, microstreaming, and jetting will be reviewed from both a theoretical and experimental perspective.
References
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Journal ArticleDOI
Current status and future potential of transdermal drug delivery
TL;DR: The already significant impact this field has made on the administration of various pharmaceuticals is discussed; limitations of the current technology are explored; methods under exploration for overcoming these limitations and the challenges ahead are discussed.
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Healing sound: the use of ultrasound in drug delivery and other therapeutic applications
TL;DR: Ultrasound, which is routinely used for diagnostic imaging applications, is now being adopted in various drug delivery and other therapeutic applications, and the principles and current status are reviewed.
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Controlled vesicle deformation and lysis by single oscillating bubbles
TL;DR: An experiment in which gentle (linear) bubble oscillations are sufficient to achieve rupture of lipid membranes and the bubble dynamics and the ensuing sonoporation can be accurately controlled.
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Noninvasive localized delivery of Herceptin to the mouse brain by MRI-guided focused ultrasound-induced blood-brain barrier disruption.
TL;DR: It is reported that Herceptin can be delivered locally and noninvasively into the mouse central nervous system through the blood- brain barrier under image guidance by using an MRI-guided focused ultrasound blood-brain barrier disruption technique.
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Direct In Vivo Visualization of Intravascular Destruction of Microbubbles by Ultrasound and its Local Effects on Tissue
TL;DR: Microbubbles can be destroyed by ultrasound, resulting in a bioeffect that could be used for local drug delivery, angiogenesis, and vascular remodeling, or for tumor destruction.