Factors Influencing the Repeated Transient Optical Droplet Vaporization Threshold and Lifetimes of Phase Change, Perfluorocarbon Nanodroplets.

Perfluorocarbon nanodroplets (PFCnDs) are sub-micrometer emulsions composed of a surfactant-encased perfluorocarbon (PFC) liquid and can be formulated to transiently vaporize through optical stimulation. However, the factors governing repeated optical droplet vaporization (ODV) have not been investigated. In this study, we employ high-frame-rate ultrasound (US) to characterize the ODV thresholds of various formulations and imaging parameters and identify those that exhibit low vaporization thresholds and repeatable vaporization.

pH-responsive ratiometric photoacoustic imaging of polyaniline nanoparticle-coated needle for targeted cancer biopsy.

Cancer microenvironment exhibits lower pH compared to healthy tissues, a characteristic which can be exploited using a pH-responsive needle to increase the accuracy of cancer biopsy. A needle, coated with pH-responsive polyaniline (PANI) nanoparticles (PANI-needle), is developed for the minimally invasive and quantitative pH analysis of tissue based on ratiometric photoacoustic (PA) imaging. The ratiometric PA signal from the PANI-needle within the 850-700 nm wavelength range shows a linear response as pH changes from 7.

Adaptive singular value decomposition filtering of high-intensity focused ultrasound interference enables real-time ultrasound-guided therapy.

High-intensity focused ultrasound (HIFU) is an emerging therapeutic tool for the effective thermal ablation of pathological tissue. For accurate localization of the target and safe control of the HIFU dosage, real-time imaging guidance during the HIFU exposure is desired. Ultrasound imaging has the capability to guide clinicians toward a lesion in real time, but is not an ideal option, as HIFU application causes strong interference, thereby substantially distorting the images used for guidance.

Precursor Heterogeneity Driven Mo-Te Nanoparticle Structural Diversification for Cancer Photo-Theranostics.

Chemical reactions between homogeneous precursors are typically used to synthesize monodisperse nanoparticles with well-controlled size and morphology. It is difficult to predict the evolved nanostructures when using two heterogeneous precursors. In this study, three types of Mo-Te nanoparticles shaped like leaves, spindles, and rice grains (denoted respectively as nanoleaf, nanospindle, and nanorice) were obtained from dextrose-mediated proton-coupled electron transfer reaction between the solid polyoxomolybdate (POM) and the ionic tellurite anion as precursors.

Usefulness of regional cerebral perfusion combined with coronary perfusion during one-stage total repair of aortic arch anomaly.

Background: We assessed whether regional cerebral perfusion is neurologically safe during long-term follow up, and evaluated the effect of our current combined coronary perfusion strategy by comparing outcomes of nonworking beating hearts and arrested hearts under regional cerebral perfusion.

Methods: From March 2000 to October 2008, 159 neonates or infants with an aortic arch anomaly underwent one-stage biventricular repair with continuous cerebral perfusion. Patients (group A, n = 111) under continuous cerebral perfusion with a nonworking beating heart using the dual-perfusion technique through the innominate artery and aortic root were compared with patients (group B, n = 48) under continuous cerebral perfusion with an arrested heart.

Midterm change of descending aortic false lumen after repair of acute type I dissection.

Background: Persistent false lumen in the descending aorta after repair of acute type I dissection adversely affects long-term prognosis. In this study, we investigated changes of the descending aortic false lumen during the midterm postoperative period.

Methods: Postoperative computed tomographic (CT) images of 122 patients who underwent conventional ascending with or without arch replacement for acute type I dissection were reviewed.