Size effect of liposomes on centimeter-deep ultrasound-switchable fluorescence imaging and ultrasound-controlled release.

Liposomes have been widely used in both medical imaging and drug delivery fields due to their excellent biocompatibility and easy surface modification. Recently our lab reported for the first-time the implementation of temperature-sensitive and indocyanine green (ICG)-encapsulated liposome microparticles for ultrasound-switchable fluorescence (USF) imaging. A previous study showed that liposome microparticles achieved USF imaging in centimeter-deep tissue.

Thermo- and pH-sensitive nanoparticles of poly (-isopropylacrylamide-decenoic acid-1-vinylimidazole) for ultrasound switchable fluorescence imaging.

We herein report the synthesis of poly (9-decenoic acid-1-vinylimidazole--isopropylacrylamide) nanoparticles containing indocyanine green (ICG) in one pot and in water phase throughout the reaction. We have shown that copolymers of 9-decenoic acid and 1-vinylimidazole, or 9-decenoic acid alone, have an enhanced sensitivity to pH values between 7.4 and 6.

Association of Medical Student Characteristics and Empathy After a Communication Workshop.

Medical education values patient-centered communication skills of responding to patient's emotions, however, guidance is limited on how to provide a well-rounded curriculum. This study examines the effect of a 90-minute communication workshop on the level of empathy of the 116 medical students who participated in the workshop. We used three psychometric categories from the Jefferson Scale of Empathy (JSE) as dependent variables.

A Biocompatible and Near-Infrared Liposome for In Vivo Ultrasound-Switchable Fluorescence Imaging.

Fluorescence imaging is a remarkable tool for molecular targeting and multicolor imaging, but it suffers from low resolution in centimeter-deep tissues. The recently developed ultrasound-switchable fluorescence (USF) imaging has overcome this challenge and achieved in vivo imaging in a mouse with help from the indocyanine green (ICG) dye encapsulated poly(N-isopropylacrylamide) (ICG-PNIPAM) contrast agent. However, the ICG-PNIPAM has shortcomings, such as concerns about cytotoxicity and blueshifted excitation and emission spectra.

Hydralazine targets cAMP-dependent protein kinase leading to sirtuin1/5 activation and lifespan extension in C. elegans.

Therapeutic activation of mitochondrial function has been suggested as an effective strategy to combat aging. Hydralazine is an FDA-approved drug used in the treatment of hypertension, heart failure and cancer. Hydralazine has been recently shown to promote lifespan in C.

Modulating the resting-state functional connectivity patterns of language processing areas in the human brain with anodal transcranial direct current stimulation applied over the Broca's area.

Cortical circuit reorganization induced by anodal transcranial direct current stimulation (tDCS) over the Broca's area of the dominant language hemisphere in 13 healthy adults was quantified by functional near-infrared spectroscopy (fNIRS). Transient cortical reorganization patterns in steady-state functional connectivity (seed-based and graph theory analysis) and temporal functional connectivity (sliding window correlation analysis) were recorded before, during, and after applying high current tDCS (1 mA, 8 min). fNIRS connectivity mapping showed that tDCS induced significantly ([Formula: see text]) increased functional connectivity between Broca's area and its neighboring cortical regions while it simultaneously decreased the connectivity to remote cortical regions.

Modulation of ultrasound-switchable fluorescence for improving signal-to-noise ratio.

Simultaneously achieving high signal-to-noise ratio (SNR) (or sensitivity) and high resolution is desired in biomedical imaging. However, conventional imaging modality has a tradeoff between SNR (or sensitivity) and resolution. We developed a method to simultaneously achieve high SNR (or sensitivity) and high resolution for fluorescence imaging in deep tissue.

A Dual-Modality System for Both Multi-Color Ultrasound-Switchable Fluorescence and Ultrasound Imaging.

Simultaneous imaging of multiple targets (SIMT) in opaque biological tissues is an important goal for molecular imaging in the future. Multi-color fluorescence imaging in deep tissues is a promising technology to reach this goal. In this work, we developed a dual-modality imaging system by combining our recently developed ultrasound-switchable fluorescence (USF) imaging technology with the conventional ultrasound (US) B-mode imaging.

Lung protection by inhalation of exogenous solubilized extracellular matrix.

Decellularized extracellular matrix (ECM) contains complex tissue-specific components that work in concert to promote tissue repair and constructive remodeling and has been used experimentally and clinically to accelerate epithelial wound repair, leading us to hypothesize that lung-derived ECM could mitigate acute lung injury. To explore the therapeutic potential of ECM for noninvasive delivery to the lung, we decellularized and solubilized porcine lung ECM, then characterized the composition, concentration, particle size and stability of the preparation. The ECM preparation at 3.

High-Resolution Ultrasound-Switchable Fluorescence Imaging in Centimeter-Deep Tissue Phantoms with High Signal-To-Noise Ratio and High Sensitivity via Novel Contrast Agents.

For many years, investigators have sought after high-resolution fluorescence imaging in centimeter-deep tissue because many interesting in vivo phenomena-such as the presence of immune system cells, tumor angiogenesis, and metastasis-may be located deep in tissue. Previously, we developed a new imaging technique to achieve high spatial resolution in sub-centimeter deep tissue phantoms named continuous-wave ultrasound-switchable fluorescence (CW-USF). The principle is to use a focused ultrasound wave to externally and locally switch on and off the fluorophore emission from a small volume (close to ultrasound focal volume).

Automated voxel classification used with atlas-guided diffuse optical tomography for assessment of functional brain networks in young and older adults.

Atlas-guided diffuse optical tomography (atlas-DOT) is a computational means to image changes in cortical hemodynamic signals during human brain activities. Graph theory analysis (GTA) is a network analysis tool commonly used in functional neuroimaging to study brain networks. Atlas-DOT has not been analyzed with GTA to derive large-scale brain connectivity/networks based on near-infrared spectroscopy (NIRS) measurements.

Are there gender differences in young vs. aging brains under risk decision-making? An optical brain imaging study.

Few research publications have reported on gender-dependent neural correlates of risk decision-making in older adults. In this study, we utilized functional near-infrared spectroscopy (fNIRS) to comprehensively investigate both age- and gender-dependent differences in neural correlates in response to a well-utilized risk decision-making protocol, the Balloon Analog Risk Task (BART). A newly-developed technique, atlas-guided diffuse optical tomography (atlas-DOT), was used to image the prefrontal cortices (PFC) of healthy subjects in two age groups (25-40 years; 60-92 years) using BART stimulation.

Motion tracking and electromyography-assisted identification of mirror hand contributions to functional near-infrared spectroscopy images acquired during a finger-tapping task performed by children with cerebral palsy.

Recent studies have demonstrated functional near-infrared spectroscopy (fNIRS) to be a viable and sensitive method for imaging sensorimotor cortex activity in children with cerebral palsy (CP). However, during unilateral finger tapping, children with CP often exhibit unintended motions in the nontapping hand, known as mirror motions, which confuse the interpretation of resulting fNIRS images. This work presents a method for separating some of the mirror motion contributions to fNIRS images and demonstrates its application to fNIRS data from four children with CP performing a finger-tapping task with mirror motions.

Tutorial on use of intraclass correlation coefficients for assessing intertest reliability and its application in functional near-infrared spectroscopy-based brain imaging.

Test-retest reliability of neuroimaging measurements is an important concern in the investigation of cognitive functions in the human brain. To date, intraclass correlation coefficients (ICCs), originally used in interrater reliability studies in behavioral sciences, have become commonly used metrics in reliability studies on neuroimaging and functional near-infrared spectroscopy (fNIRS). However, as there are six popular forms of ICC, the adequateness of the comprehensive understanding of ICCs will affect how one may appropriately select, use, and interpret ICCs toward a reliability study.

Evaluation of cortical plasticity in children with cerebral palsy undergoing constraint-induced movement therapy based on functional near-infrared spectroscopy.

Sensorimotor cortex plasticity induced by constraint-induced movement therapy (CIMT) in six children (10.2±2.1 years old) with hemiplegic cerebral palsy was assessed by functional near-infrared spectroscopy (fNIRS).

Influence of body mass index on the biomechanical properties of the human prolapsed anterior vaginal wall.

Introduction And Hypothesis: We report the influence of body mass index (BMI) on the biomechanical properties of human prolapsed anterior vaginal wall (AVW) tissue samples. We hypothesize that women with AVW prolapse would have the same vaginal wall biomechanical properties regardless of their weight.

Methods: Following Institutional Review Board approval, age-comparable postmenopausal women with symptomatic stage II-III AVW prolapse underwent excision of a short vaginal wall sample during transvaginal prolapse repair.

Re-evaluation of biotin-streptavidin conjugation in Förster resonance energy transfer applications.

Bioaffinity conjugation between streptavidin (SA) and biotin has been widely used to link donors and acceptors for investigating the distance-dependent Förster resonance energy transfer (FRET). When studying a commonly used FRET system of (QD-SA)-(biotin-DNA-dye) [donor: quantum dot (QD); acceptor: small organic fluorescent dye; and linker: deoxyribose nucleic acid (DNA) molecule via SA-biotin conjugation], however, a contradictory finding was recently reported in the literature. It was found that the FRET lost its dependence on the number of DNA base pairs when using a phosphate-buffered saline (PBS) solution.

Ultrasound-modulated fluorescence based on fluorescent microbubbles.

Ultrasound-modulated fluorescence (UMF) imaging has been proposed to provide fluorescent contrast while maintaining ultrasound resolution in an optical-scattering medium (such as biological tissue). The major challenge is to extract the weakly modulated fluorescent signal from a bright and unmodulated background. UMF was experimentally demonstrated based on fluorophore-labeled microbubble contrast agents.

Parallel recognition of cancer cells using an addressable array of solid-state micropores.

Early stage detection and precise quantification of circulating tumor cells (CTCs) in the peripheral blood of cancer patients are important for early diagnosis. Early diagnosis improves the effectiveness of the therapy and results in better prognosis. Several techniques have been used for CTC detection but are limited by their need for dye tagging, low throughput and lack of statistical reliability at single cell level.

Prostate cancer detection using combined auto-fluorescence and light reflectance spectroscopy: ex vivo study of human prostates.

This study was conducted to evaluate the capability of detecting prostate cancer (PCa) using auto-fluorescence lifetime spectroscopy (AFLS) and light reflectance spectroscopy (LRS). AFLS used excitation at 447 nm with four emission wavelengths (532, 562, 632, and 684 nm), where their lifetimes and weights were analyzed using a double exponent model. LRS was measured between 500 and 840 nm and analyzed by a quantitative model to determine hemoglobin concentrations and light scattering.

In vitro cytotoxicity evaluation of four vital pulp therapy materials on l929 fibroblasts.

The aim of this study was to evaluate cytotoxicity of direct pulp capping materials such as Dycal, Life, ProRoot MTA, and Super-Bond C&B on L929 fibroblasts. Freshly mixed or set materials were prepared and eluted by incubation with cell culture medium for working time period (fresh) or for 6 hours (set). The cells were exposed to media containing elutes for 24 hours, after which the cell survival was evaluated by MTS assays.

3D structural integrity and interactions of single-stranded protein-binding DNA in a functionalized nanopore.

Biomarker-binding nucleotide sequences, like aptamers, have gained recent attention in cancer cell isolation and detection works. Self-assembly and 3D conformation of aptamers enable them to selectively capture and bind diseased cells and related biomarkers. One mode of utilizing such an extraordinary selective property of the aptamers is by grafting these in nanopores.

Atlas-guided volumetric diffuse optical tomography enhanced by generalized linear model analysis to image risk decision-making responses in young adults.

Diffuse optical tomography (DOT) is a variant of functional near infrared spectroscopy and has the capability of mapping or reconstructing three dimensional (3D) hemodynamic changes due to brain activity. Common methods used in DOT image analysis to define brain activation have limitations because the selection of activation period is relatively subjective. General linear model (GLM)-based analysis can overcome this limitation.