Pressure estimation of ultra-high frequency ultrasound using gas vesicles.

Acoustic microscopy uses ultra-high frequency (UHF) ultrasound transducers over 80 MHz to perform high-resolution imaging. The pressure output of these transducers is unknown, as commercial calibrated hydrophones can measure pressure for transducers with frequencies only up to 80 MHz. This study used gas vesicle nanostructures (GVs) that collapse at 571 kPa to estimate the pressure of UHF transducers at 40, 80, 200, and 375 MHz.

Photoacoustic imaging of metabolic activities across biological length scales.

Imaging is ubiquitous with biomedical research and discovery. This article surveys the role of imaging in our understanding of metabolism, and introduces photoacoustic imaging as a compelling candidate for providing high-resolution, label-free, and real-time insights into metabolic processes. As a rapidly evolving modality, photoacoustics holds promising preclinical and clinical potential in imaging of metabolism as well as metabolism-related changes.

RBE-based dose planning, and calculation of TCP and NTCP with gold nanoparticles for intermediate photon energy in pancreatic cancer.

This study simulated the potential of gold nanoparticles (GNPs) to improve the effectiveness of radiation therapy in pancreatic cancer cases. The purpose of this study was to assess the impact of GNPs on tumor control probability (TCP) and normal tissue complication probability (NTCP) in pancreatic cancer cases undergoing radiation therapy. The work aimed to compare treatment plans generated with a novel 2.

Interaction of ultrasonically driven bubble with a soft tissue-like boundary.

This study investigates the size-dependent dynamics of bubbles and their interaction with soft boundaries under various ultrasound (US) conditions. We found that bubble behavior is influenced by size, with smaller bubbles displaying reduced inertial motion in similar ultrasound environments. Detailed analyses of three bubble sizes (1.

Influence of the liquid ionic strength on the resonance frequency and shell parameters of lipid-coated microbubbles.

The correct measurement of the resonance frequency and shell properties of coated microbubbles (MBs) is essential in understanding and optimizing their response to ultrasound (US) exposure parameters. In diagnostic and therapeutic ultrasound, MBs are typically surrounded by blood; however, the influence of the medium charges on the MB resonance frequency has not been systematically studied using controlled measurements. This study aims to measure the medium charge interactions on MB behavior by measuring the frequency-dependent attenuation of the same size MBs in mediums with different charge densities.

Encapsulation of in Water-in-Water Microdroplets to Study the Worm Viability: Alternative Avenue to Manipulate Microdroplet Environment.

Due to the great biocompatibility of the aqueous two phase system (ATPS), biological cells have been widely encapsulated in ATPS microdroplets (diameter < 50 . However, the immobilization of relatively large multicellular organisms such as in ATPS droplets remains challenging as the spontaneous generation of droplets greater than 200 μm is difficult without external perturbations. In this study, we utilize a microneedle-assisted coflow microfludic channel to passively form ATPS microdroplets larger than 200 μm and successfully entrap in the microdroplets.

Controlled Tempering of Lipid Concentration and Microbubble Shrinkage as a Possible Mechanism for Fine-Tuning Microbubble Size and Shell Properties.

The acoustic response of microbubbles (MBs) depends on their resonance frequency, which is dependent on the MB size and shell properties. Monodisperse MBs with tunable shell properties are thus desirable for optimizing and controlling the MB behavior in acoustics applications. By utilizing a novel microfluidic method that uses lipid concentration to control MB shrinkage, we generated monodisperse MBs of four different initial diameters at three lipid concentrations (5.

Detection of lung cancer metastasis from blood using L-MISC nanosensor: Targeting circulating metastatic cues for improved diagnosis.

Metastatic lung cancers are considered one of the most clinically significant malignancies, comprising about 40% of deaths caused by cancers. Detection of lung cancer metastasis prior to symptomatic relapse is critical for timely diagnosis and clinical management. The onset of cancer metastasis is indicated by the manifestation of tumor-shed signatures from the primary tumor in peripheral circulation.

High throughput microfluidic nanobubble generation by microporous membrane integration and controlled bubble shrinkage.

Microfluidics has recently been proposed as a viable method for producing bulk nanobubbles for use in various applications. The portability, compact size, and capacity to precisely control fluids on a small scale are a few of the benefits of microfluidics that may be exploited to create customized bulk nanobubbles. However, despite the potential of microfluidic nanobubble generation, low throughput and limited nanobubble concentration remain challenging for microfluidics.

Microfluidic nanobubbles: observations of a sudden contraction of microbubbles into nanobubbles.

Microfluidic devices are often utilized to generate uniform-size microbubbles. In most microfluidic bubble generation experiments, once the bubbles are formed the gas inside the bubbles begin to dissolve into the surrounding aqueous environment. The bubbles shrink until they attain an equilibrium size dictated by the concentration and type of amphiphilic molecules stabilizing the gas-liquid interface.

Radioenhancement with the Combination of Docetaxel and Ultrasound Microbubbles: In Vivo Prostate Cancer.

Using an in vitro prostate cancer model, we previously demonstrated the significant enhancement of radiotherapy (XRT) with the combined treatment of docetaxel (Taxotere; TXT) and ultrasound-microbubbles (USMB). Here, we extend these findings to an in vivo cancer model. Severe combined immune-deficient male mice were xenografted with the PC-3 prostate cancer cell line in the hind leg and treated with USMB, TXT, radiotherapy (XRT), and their combinations.

DNA Methylation Signatures of Tumor-Associated Natural Killer Cells with Self-Functionalized Nanosensor Enable Colorectal Cancer Diagnosis.

Natural killer (NK) cells undergo multiple DNA genomic alterations, especially methylation-based modifications that affect activation and function. Several epigenetic modifier markers have been targeted for immunotherapy to date, but the possibility of cancer diagnosis using NK cell's DNA has been overlooked. Here, we investigated the potential use of NK cell DNA genome modifications as markers for the diagnosis of colorectal cancer (CRC) and validated their efficacy in CRC patients.

Mapping Immune-Tumor Bidirectional Dialogue Using Ultrasensitive Nanosensors for Accurate Diagnosis of Lung Cancer.

Lung cancer is one of the most common cancers with high mortality worldwide despite the development of molecularly targeted therapies and immunotherapies. A significant challenge in managing lung cancer is the accurate diagnosis of cancerous lesions owing to the lack of sensitive and specific biomarkers. The current procedure necessitates an invasive tissue biopsy for diagnosis and molecular subtyping, which presents patients with risk, morbidity, anxiety, and high false-positive rates.

Label-Free Saliva Test for Rapid Detection of Coronavirus Using Nanosensor-Enabled SERS.

The recent COVID-19 pandemic has highlighted the inadequacies of existing diagnostic techniques and the need for rapid and accurate diagnostic systems. Although molecular tests such as RT-PCR are the gold standard, they cannot be employed as point-of-care testing systems. Hence, a rapid, noninvasive diagnostic technique such as Surface-enhanced Raman scattering (SERS) is a promising analytical technique for rapid molecular or viral diagnosis.

Air-Coupled Photoacoustic Detection of Airborne Particulates.

In this study, we present a novel method to detect airborne particulates using air-coupled photoacoustics, with a goal toward detecting viral content in respiratory droplets. The peak photoacoustic frequency emitted from micrometer-sized particulates is over 1000 MHz, but at this frequency, the signals are highly attenuated in air. Measurements were taken using a thin planar absorber and ultrasound transducers with peak sensitivity between 50 kHz and 2000 kHz and a 532 nm pulsed laser to determine the optimum detection frequency.

Assessing engineered tissues and biomaterials using ultrasound imaging: In vitro and in vivo applications.

Quantitative assessment of the structural, functional, and mechanical properties of engineered tissues and biomaterials is fundamental to their development for regenerative medicine applications. Ultrasound (US) imaging is a non-invasive, non-destructive, and cost-effective technique capable of longitudinal and quantitative monitoring of tissue structure and function across centimeter to sub-micron length scales. Here we present the fundamentals of US to contextualize its application for the assessment of biomaterials and engineered tissues, both in vivo and in vitro.

Microfluidically-generated Encapsulated Spheroids (μ-GELS): An All-Aqueous Droplet Microfluidics Platform for Multicellular Spheroids Generation.

Spheroids are three-dimensional clusters of cells that serve as in vitro tumor models to recapitulate in vivo morphology. A limitation of many existing on-chip platforms for spheroid formation is the use of cytotoxic organic solvents as the continuous phase in droplet generation processes. All-aqueous methods do not contain cytotoxic organic solvents but have so far been unable to achieve complete hydrogel gelation on chip.

High-frequency quantitative ultrasound for the assessment of the acoustic properties of engineered tissues in vitro.

Acoustic properties of biomaterials and engineered tissues reflect their structure and cellularity. High-frequency ultrasound (US) can non-invasively characterize and monitor these properties with sub-millimetre resolution. We present an approach to estimate the speed of sound, acoustic impedance, and acoustic attenuation of cell-laden hydrogels that accounts for frequency-dependent effects of attenuation in coupling media, hydrogel thickness, and interfacial transmission/reflection coefficients of US waves, all of which can bias attenuation estimates.

Dual-Purpose 3D-Silica Nanostructure Matrix for Rapid Epigenetic Reprogramming of Tumor Cell to Cancer Stem Cell Spheroid.

Cancer stem cells (CSCs), a rare subpopulation responsible for tumorigenesis and therapeutic resistance, are difficult to characterize and isolate. Conventional method of growing CSCs takes up to 2-8 weeks inhibiting the rate of research. Therefore, rapid reprogramming (RR) of tumor cells into CSCs is crucial to accelerate the stem cell oncology research.

Structure-rheology relationship in monoolein liquid crystals.

Hypotheses: Monoolein liquid crystals find use in foods and pharmaceuticals. Our hypotheses were: (a) liquid crystal symmetry dominates yielding and large deformation, and (b) strain rate frequency superposition (SRFS) may be used to determine mesophase long and short relaxation times.

Experiments: Liquid crystal microstructure and rheology were characterised as a function of temperature and composition.

Controlled Shrinkage of Microfluidically Generated Microbubbles by Tuning Lipid Concentration.

Monodisperse microbubbles with diameters less than 10 μm are desirable in several ultrasound imaging and therapeutic delivery applications. However, conventional approaches to synthesize microbubbles, which are usually agitation-based, produce polydisperse bubbles that are less desirable because of their heterogeneous response when exposed to an ultrasound field. Microfluidics technology has the unique advantage of generating size-controlled monodisperse microbubbles, and it is now well established that the diameter of microfluidically made microbubbles can be tuned by varying the liquid flow rate, gas pressure, and dimensions of the microfluidic channel.

Molecular Crosstalk between T Cells and Tumor Uncovers GBM-Specific T Cell Signatures in Blood: Noninvasive GBM Diagnosis Using Immunosensors.

Glioblastoma (GBM) is the most common and aggressive stage IV brain cancer with a poor prognosis and survival rate. The blood-brain barrier (BBB) in GBM prevents the entry and exit of biomarkers, limiting its treatment options. Hence, GBM diagnosis is pivotal for timely clinical management.

Glioblastoma Associated Natural Killer Cell EVs Generating Tumour-Specific Signatures: Noninvasive GBM Liquid Biopsy with Self-Functionalized Quantum Probes.

Diagnosis of glioblastoma (GBM) poses a recurring struggle due to many factors, including the presence of the blood-brain barrier (BBB) in addition to the significant tumor heterogeneity. Natural killer (NK) cells of the innate immune system are the primary immune surveillance mechanism for GBM and identify GBM tumors without any previous sensitization. The metabolic reprogramming of NK cells during GBM association is expected to be reflected in its extracellular vesicles.