Stable Thermally-Modulated Nanodroplet Ultrasound Contrast Agents

Liquid perfluorocarbon-based nanodroplets are stable enough to be used in extravascular imaging, but provide limited contrast enhancement due to their small size, incompressible core, and small acoustic impedance mismatch with biological fluids. Here we show a novel approach to overcoming this limitation by using a heating–cooling cycle, which we will refer to as thermal modulation (TM), to induce echogenicity of otherwise stable but poorly echogenic nanodroplets without triggering a transient phase shift. We apply thermal modulation to high-boiling point tetradecafluorohexane (TDFH) nanodroplets stabilized with a bovine serum albumin (BSA) shell. BSA-TDFH nanodroplets with an average diameter under 300 nanometers showed an 11.9 ± 5.4 mean fold increase in echogenicity on the B-mode and a 13.9 ± 6.9 increase on the nonlinear contrast (NLC) mode after thermal modulation. Once activated, the particles maintained their enhanced echogenicity (p < 0.001) for at least 13 h while retaining their nanoscale size. Our data indicate that thermally modulated nanodroplets can potentially serve as theranostic agents or sensors for various applications of contrast-enhanced ultrasound.

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Bile acid analysis in biological fluids: a novel approach

The Journal of Lipid Research ◽

10.1016/s0022-2275(20)37165-0 ◽

1997 ◽

Vol 38 (9) ◽

pp. 1906-1912

Author(s):

K Budai ◽

N B Javitt

Keyword(s):

Bile Acid ◽

Biological Fluids ◽

Novel Approach

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NANOmetric BIO-Banked MSC-Derived Exosome (NANOBIOME) as a Novel Approach to Regenerative Medicine

Journal of Clinical Medicine ◽

10.3390/jcm7100357 ◽

2018 ◽

Vol 7 (10) ◽

pp. 357 ◽

Cited By ~ 7

Author(s):

Bruna Codispoti ◽

Massimo Marrelli ◽

Francesco Paduano ◽

Marco Tatullo

Keyword(s):

Plasma Membrane ◽

Regenerative Medicine ◽

Extracellular Vesicles ◽

Biological Fluids ◽

Cell Types ◽

Endogenous Factors ◽

Cell Lineages ◽

Novel Approach ◽

Therapeutic Uses ◽

Technical Issues

Mesenchymal stem cells (MSCs) are well known for their great potential in clinical applications. In fact, MSCs can differentiate into several cell lineages and show paracrine behavior by releasing endogenous factors that stimulate tissue repair and modulate local immune response. Each MSC type is affected by specific biobanking issues—technical issues as well as regulatory and ethical concerns—thus making it quite tricky to safely and commonly use MSC banking for swift regenerative applications. Extracellular vesicles (EVs) include a group of 150–1000 nm vesicles that are released by budding from the plasma membrane into biological fluids and/or in the culture medium from varied and heterogenic cell types. EVs consist of various vesicle types that are defined with different nomenclature such as exosomes, shedding vesicles, nanoparticles, microvesicles and apoptotic bodies. Ectosomes, micro- and nanoparticles generally refer to the direct release of single vesicles from the plasma membrane. While many studies describe exosomes as deriving from multivesicular bodies, solid evidence about the origin of EVs is often lacking. Extracellular vesicles represent an important portion of the cell secretome. Their numerous properties can be used for diagnostic, prognostic, and therapeutic uses, so EVs are considered to be innovative and smart theranostic tools. The aim of this review is to investigate the usefulness of exosomes as carriers of the whole information panel characterizing the use of MSCs in regenerative medicine. Our purpose is to make a step forward in the development of the NANOmetric BIO-banked MSC-derived Exosome (NANOBIOME).

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A Novel Approach to Nanoscale Materials Synthesis Using Industrial Laser Processing of Organosilazane Liquid Precursors

MRS Proceedings ◽

10.1557/proc-206-557 ◽

1990 ◽

Vol 206 ◽

Author(s):

Tongsan D. Xiao ◽

Peter R. Strutt ◽

Kenneth E. Gonsalves

Keyword(s):

Ceramic Powder ◽

Average Diameter ◽

Current Approach ◽

Powder Materials ◽

Materials Synthesis ◽

Laser Plume ◽

New Approach ◽

Novel Approach ◽

Liquid Precursors ◽

Short Time

ABSTRACTA new approach has been developed for the synthesis of nanoscale ceramic powder materials from liquid organosilazane precursors. This technique, by exploiting fast kinetic chemical and physical reactions, makes it possible to synthesize significant quantities of material in a relatively short time. In the current approach aerosols of a silazane monomer, (CH3SiHNH)n, (n = 3 or 4), of mol. wt. 280–320, are injected into the beam of a cw industrial CO2 laser to obtain nanoscale ceramic powders. Injection of the aerosol into the laser-beam results in a high-temperature plume. Rapid condensation of the molecular precursor species emerging from the laser plume results in the formation of preceramic polymer particles, with an average diameter of 62 nm. One attractive feature of this process is that 70 wt.% of the liquid precursor is converted into nanoscale powders. Another feature is that only a further 10 wt.% loss occurs during post thermal treatment to form the end-product.

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Recent Experiences and Advances in Contrast-Enhanced Subharmonic Ultrasound

BioMed Research International ◽

10.1155/2015/640397 ◽

2015 ◽

Vol 2015 ◽

pp. 1-6 ◽

Cited By ~ 9

Author(s):

John R. Eisenbrey ◽

Anush Sridharan ◽

Ji-Bin Liu ◽

Flemming Forsberg

Keyword(s):

Contrast Agents ◽

Tumor Imaging ◽

Three Dimensional ◽

Ultrasound Contrast Agents ◽

Surrounding Tissue ◽

Contrast Enhanced Ultrasound ◽

Ultrasound Contrast ◽

Contrast Enhanced ◽

Subharmonic Response

Nonlinear contrast-enhanced ultrasound imaging schemes strive to suppress tissue signals in order to better visualize nonlinear signals from blood-pooling ultrasound contrast agents. Because tissue does not generate a subharmonic response (i.e., signal at half the transmit frequency), subharmonic imaging has been proposed as a method for isolating ultrasound microbubble signals while suppressing surrounding tissue signals. In this paper, we summarize recent advances in the use of subharmonic imagingin vivo. These advances include the implementation of subharmonic imaging on linear and curvilinear arrays, intravascular probes, and three-dimensional probes for breast, renal, liver, plaque, and tumor imaging.

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Incidental nonfunctioning pancreatic neuroendocrine tumors: Contrast enhanced ultrasound features in diagnosis

Clinical Hemorheology and Microcirculation ◽

10.3233/ch-211269 ◽

2021 ◽

pp. 1-10

Author(s):

Daohui Yang ◽

Dansong Wang ◽

Yijie Qiu ◽

Xiaofan Tian ◽

Dan Zuo ◽

...

Keyword(s):

Neuroendocrine Tumors ◽

Clinical Decision Making ◽

Ultrasound Contrast Agents ◽

Arterial Phase ◽

Control Group ◽

Pancreatic Neuroendocrine Tumors ◽

Contrast Enhanced Ultrasound ◽

Color Flow ◽

Color Flow Imaging ◽

Contrast Enhanced

AIM: Preoperative suspicion of malignancy in nonfunctioning pancreatic neuroendocrine tumors (pNETs) is mostly based on tumor size. We retrospectively analyzed the contrast enhanced ultrasound (CEUS) features of a series of histopathologically proved nonfunctioning pNETs. METHODS: In this retrospective study, 37 surgery and histologically proved nonfunctioning pNETs were included. All pNETs lesions were incidentally detected by transabdominal ultrasound. B mode ultrasound (BMUS) and CEUS features were reviewed and analyzed. 52 histopathologically proved pancreatic ductal adenocarcinoma (PDACs) lesions were included as a control group. RESULTS: All nonfunctioning pNETs patients showed no typical clinical symptoms. No significant differences were observed in size, echogenicity or internal color flow imaging signal between pNETs and PDAC patients (P > 0.05). Most of nonfunctioning pNETs showed a well-defined tumor margin. The presence of pancreatic duct dilatation was less frequently observed in nonfunctioning pNETs patients (P < 0.05). After injection of ultrasound contrast agents, homogeneous enhancement was more commonly observed in nonfunctioning pNETs group (P < 0.05). During arterial phase of CEUS, most of nonfunctioning pNETs were hyper- or isoenhanced (32/37, 86.5%), whereas most of PDACs were hypoenhanced (34/52, 65.4%) (P < 0.05). Nonenhanced necrosis area was more commonly detected in PDACs (P = 0.012). CONCLUSIONS: CEUS features are helpful for preoperative non-invasive differential diagnosis of nonfunctioning pNETs, assisting further clinical decision-making process.

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Window-Modulated Compounding Nakagami Parameter Ratio Approach for Assessing Muscle Perfusion with Contrast-Enhanced Ultrasound Imaging

Sensors ◽

10.3390/s20123584 ◽

2020 ◽

Vol 20 (12) ◽

pp. 3584

Author(s):

Huang-Chen Lin ◽

Shyh-Hau Wang

Keyword(s):

Contrast Agents ◽

Ultrasound Imaging ◽

Ultrasound Contrast Agents ◽

Muscle Disease ◽

Contrast Enhanced Ultrasound ◽

Time Intensity Curve ◽

Muscle Perfusion ◽

Ultrasound Contrast ◽

Parameter Ratio ◽

Contrast Enhanced

The assessment of microvascular perfusion is essential for the diagnosis of a specific muscle disease. In comparison with the current available medical modalities, the contrast-enhanced ultrasound imaging is the simplest and fastest means for probing the tissue perfusion. Specifically, the perfusion parameters estimated from the ultrasound time-intensity curve (TIC) and statistics-based time–Nakagami parameter curve (TNC) approaches were found able to quantify the perfusion. However, due to insufficient tolerance on tissue clutters and subresolvable effects, these approaches remain short of reproducibility and robustness. Consequently, the window-modulated compounding (WMC) Nakagami parameter ratio imaging was proposed to alleviate these effects, by taking the ratio of WMC Nakagami parameters corresponding to the incidence of two different acoustic pressures from an employed transducer. The time–Nakagami parameter ratio curve (TNRC) approach was also developed to estimate perfusion parameters. Measurements for the assessment of muscle perfusion were performed from the flow phantom and animal subjects administrated with a bolus of ultrasound contrast agents. The TNRC approach demonstrated better sensitivity and tolerance of tissue clutters than those of TIC and TNC. The fusion image with the WMC Nakagami parameter ratio and B-mode images indicated that both the tissue structures and perfusion properties of ultrasound contrast agents may be better discerned.

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EFSUMB 2020 Proposal for a Contrast-Enhanced Ultrasound-Adapted Bosniak Cyst Categorization – Position Statement

Ultraschall in der Medizin - European Journal of Ultrasound ◽

10.1055/a-1300-1727 ◽

2020 ◽

Author(s):

Vito Cantisani ◽

Michele Bertolotto ◽

Dirk-André Clevert ◽

Jean-Michel Correas ◽

Francesco Maria Drudi ◽

...

Keyword(s):

Contrast Agents ◽

Task Force ◽

Position Statement ◽

Ultrasound Contrast Agents ◽

Renal Lesions ◽

Ultrasound Contrast ◽

Contrast Enhanced ◽

Enhanced Computed Tomography ◽

Contrast Enhanced Computed Tomography ◽

Cystic Renal Lesions

AbstractThe well-established Bosniak renal cyst classification is based on contrast-enhanced computed tomography determining the malignant potential of cystic renal lesions. Ultrasound has not been incorporated into this pathway. However, the development of ultrasound contrast agents coupled with the superior resolution of ultrasound makes it possible to redefine the imaging of cystic renal lesions. In this position statement, an EFSUMB Expert Task Force reviews, analyzes, and describes the accumulated knowledge and limitations and presents the current position on the use of ultrasound contrast agents in the evaluation of cystic renal lesions.

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Modulatory Effect of Citrate Reduced Gold and Biosynthesized Silver Nanoparticles on α-Amylase Activity

Journal of Nanoparticles ◽

10.1155/2015/829718 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 6

Author(s):

Kantrao Saware ◽

Ravindra Mahadappa Aurade ◽

P. D. Kamala Jayanthi ◽

Venkataraman Abbaraju

Keyword(s):

Gold Nanoparticles ◽

Silver Nanoparticles ◽

Amylase Activity ◽

Temperature Stability ◽

Fold Increase ◽

Free Enzyme ◽

Catalytic Function ◽

Ficus Benghalensis ◽

Novel Approach ◽

Immobilization Of Enzymes

Amylase is one of the important digestive enzymes involved in hydrolysis of starch. In this paper, we describe a novel approach to study the interaction of amylase enzyme with gold nanoparticles (AuNPs) and silver nanoparticles (AgNPs) and checked its catalytic function. AuNPs are synthesized using citrate reduction method and AgNPs were synthesized using biological route employing Ficus benghalensis and Ficus religiosa leaf extract as a reducing and stabilizing agent to reduce silver nitrate to silver atoms. A modulatory effect of nanoparticles on amylase activity was observed. Gold nanoparticles are excellent biocompatible surfaces for the immobilization of enzymes. Immobilized amylase showed 1- to 2-fold increase of activity compared to free enzyme. The biocatalytic activity of amylase in the bioconjugate was marginally enhanced relative to the free enzyme in solution. The bioconjugate material also showed significantly enhanced pH and temperature stability. The results indicate that the present study paves way for the modulator degradation of starch by the enzyme with AuNPs and biogenic AgNPs, which is a promising application in the medical and food industry.

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Development and characterization of microsatellite markers in Cynara cardunculus L.

Genome ◽

10.1139/g04-111 ◽

2005 ◽

Vol 48 (2) ◽

pp. 217-225 ◽

Cited By ~ 38

Author(s):

Alberto Acquadro ◽

Ezio Portis ◽

David Lee ◽

Paolo Donini ◽

Sergio Lanteri

Keyword(s):

Molecular Markers ◽

Fold Increase ◽

The United States ◽

Enriched Library ◽

Globe Artichoke ◽

Cynara Cardunculus ◽

Principal Coordinates Analysis ◽

Principal Coordinates ◽

Novel Approach ◽

Wild Cardoon

Cynara cardunculus L. is a species native to the Mediterranean basin that comprises 2 crops, globe artichoke (var. scolymus L.) and cultivated cardoon (var. altilis DC), as well as wild cardoon (var. sylvestris (Lamk) Fiori). Globe artichoke represents an important component of the South European agricultural economy but is also cultivated in North Africa, the Near East, South America, the United States, and China. Breeding activities and molecular marker studies have been, to date, extremely limited. Better knowledge of the genome of the species might be gained by developing a range of molecular markers. Here, we report on the development of 14 microsatellites (simple sequence repeats (SSRs)) through a novel approach that we have defined as the microsatellite amplified library (MAL). The approach represents a combination of amplified fragment length polymorphism and a primer extension based enriched library, is rapid, and requires no hybridization enrichment steps. The technique provided a ~40-fold increase in the efficiency of SSR identification compared with conventional library procedures. The developed SSRs were applied for genotyping 36 accessions of C. cardunculus, including a core of 27 varietal types of globe artichoke, 3 accessions of cultivated cardoon, and 6 Sicilian accessions of wild cardoon. Principal coordinates analysis made it possible to differentiate both cultivated and wild forms from each other.Key words: globe artichoke, wild and cultivated cardoon, molecular markers, AFLP, MAL (microsatellite amplified library).

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