The novel amphipilic conjugate of a calix[4]arene with four Gd-1,4,7,10- tetra(carboxymethyl)-1,4,7,10-tetraazacyclododecane (DOTA) chelates has potential as a magnetic resonance imaging contrast agent, both in its monomeric and in its micellar form. The system, illustrated here with its nuclear magnetic relaxation profile, shows good relaxivities, thanks to its high rigidity.An amphiphilic ...

Getting FIT: A bispherical (19)F imaging tracer, (19)FIT, was designed and synthesized. (19)FIT is advantageous over perfluorocarbon-based (19)F imaging agents, as it is not retained in the organs and does not require complex formulation procedures. Imaging agents such as (19)FIT can lead to (19)F magnetic resonance imaging (MRI) playing an ...

BACKGROUND: Liposomal-based gadolinium (Gd) nanoparticles have elicited significant interest for use as blood pool and molecular magnetic resonance imaging (MRI) contrast agents. Previous generations of liposomal MR agents contained gadolinium-chelates either within the interior of liposomes (core-encapsulated gadolinium liposomes) or presented on the surface of liposomes (surface-conjugated gadolinium liposomes). We ...

A long circulating liposomal, nanoscale blood pool agent encapsulating traditional iodinated contrast agent (65 mg I/mL) was used for micro-computed tomography (CT) imaging of rats implanted with R3230AC mammary carcinoma. Three-dimensional vascular architecture of tumors was imaged at 100-micron isotropic resolution. The image data showed good qualitative correlation with pathologic ...

The aim of this work was to map E-selectin expression in a traumatic brain injury model using a newly-designed MR contrast agent. Iron cores, responsible for susceptibility effects and therefore used as T2* contrast agents, need to be coated in order to be stabilized and need to be targeted to ...

We report an unexpected result obtained using chemical mapping on the new, aberration corrected Nion UltraSTEM at Daresbury. Using different energy windows above the L2,3 edge in 011 silicon to map the position of the atomic columns we find a contrast reversal which produces an apparent and misleading translation of ...

Imaging techniques are evolving continuously with refinements of existing machines and discovery of new techniques. Ultrasonography (US) is now able to achieve more detail in image definition through the use of very-high-frequency transducers. These can be coupled to US contrast agents to increase the sensitivity of Doppler in imaging synovial ...

Dual labeled liposomes, carrying both paramagnetic and fluorescent lipids, were recently proposed as potent contrast agents for MR molecular imaging. These nanoparticles are coated with poly(ethylene glycol) (PEG) to increase their blood circulation half-life, which should allow extensive accumulation at the targeted site. To eliminate nonspecific blood pool signal from ...

For pharmacokinetic modeling of tissue physiology, there is great interest in measuring the arterial input function (AIF) from dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) using paramagnetic contrast agents. Due to relaxation effects, the measured signal is a nonlinear function of the injected contrast agent concentration and depends on sequence ...

Radiocontrast exposure has now become an important cause of iatrogenic acute kidney injury (AKI) in hospitalized patients due to an increase in the number of diagnostic and interventional procedures done. Gadolinium, a well-known paramagnetic contrast agent used primarily for magnetic resonance imaging (MRI), has attracted a lot of attention for ...

Contrast agents targeted to molecular markers of disease are currently being developed with the goal of identifying disease early and evaluating treatment effectiveness using noninvasive imaging modalities such as MRI. Pharmacokinetic profiling of the binding of targeted contrast agents, while theoretically possible with MRI, has thus far only been demonstrated ...

Angiogenic, that is, newly formed, blood vessels play an important role in tumor growth and metastasis and are a potential target for tumor treatment. In previous studies, the alpha(v)beta(3) integrin, which is strongly expressed in angiogenic vessels, has been used as a target for Arg-Gly-Asp (RGD)-functionalized nanoparticulate contrast agents for ...

OBJECTIVE: With the introduction of a newly approved MR contrast agent across a health care system encompassing 13 hospitals and associated imaging centers, the opportunity arose to compare the rates of adverse reactions in seven of these facilities with reactions reported in the literature. Data were collected to assess the ...

X-ray based computed tomography (CT) is among the most convenient imaging/diagnostic tools in hospitals today in terms of availability, efficiency, and cost. However, in contrast to magnetic resonance imaging (MRI) and various nuclear medicine imaging modalities, CT is not considered a molecular imaging modality since targeted and molecularly specific contrast ...

Neurogenesis occurs at the subependymal zone (SEZ) of the adult brain. Neural progenitor cells give rise to neuroblasts, which migrate to the olfactory bulb (OB) via the rostral migratory stream (RMS). Development of methods capable of labelling and tracking these cells in vivo would be of great benefit to the ...

We report two prototype Ln(3+) complexes that address requirements for both MRI and luminescence imaging and we demonstrate that the presence of two H(2)O molecules bound to the Ln(3+), beneficial for MRI applications of the Gd(3+) analogue, is not a major limitation for the development of NIR luminescent agents.

PURPOSE: To evaluate the clinical feasibility and accuracy of 64-section multidetector computed tomography (CT) compared with transesophageal echocardiography (TEE) for diagnosis of a patent foramen ovale (PFO). MATERIALS AND METHODS: Institutional review board approval was obtained for this retrospective study. The study included 152 consecutive stroke patients (mean age, 61.7 ...

Recent advances in the design of fluorinated nanoparticles for molecular magnetic resonance imaging (MRI) have enabled specific detection of (19)F nuclei, providing unique and quantifiable spectral signatures. However, a pressing need for signal enhancement exists because the total (19)F in imaging voxels is often limited. By directly incorporating a relaxation ...

Gadolinium-based contrast agents were for many years considered safe, but this is no longer the case. The least stable agents may trigger the development of nephrogenic systemic fibrosis (NSF), a generalized fibrotic disorder, in renal failure patients. The use of gadodiamide and gadopentetate dimeglumine is now contraindicated in Europe and ...

We present simultaneous measurement of enhancement kinetics of an optical and a magnetic resonance (MR) contrast agent in a small animal breast tumor model (R3230 ac) using a combined MR-diffuse optical tomographic (MR-DOT) imaging system. A mixture of a small molecular-weight MR contrast agent gadolinium-diethylene-triamine-pentaacetic acid (Gd-DTPA) and a large ...

OBJECTIVE: This study was designed to determine the optimal mixture ratio of gadolinium and iodinated contrast agent for simultaneous direct MR arthrography and CT arthrography. MATERIALS AND METHODS: An in vitro study was performed utilizing mixtures of gadolinium at six different concentrations (0.625, 1.25, 2.5, 5.0, 10 and 20 mmol/L) ...

A novel magnetic resonance imaging (MRI) contrast agent containing Herceptin is reported. The surfaces of superparamagnetic iron oxide nanoparticles were modified with dextran and conjugated with Herceptin (Herceptin-nanoparticles) to improve their dispersion, magnetization, and targeting of the specific receptors on cells. From analytical results, we found that Herceptin-nanoparticles were well ...

We have developed a new type of ultrasound (US) contrast agent, consisting of a gas core, a layer of superparamagnetic iron oxide Fe(3)O(4) nanoparticles (SPIO) and an oil in water outermost layer. The newly developed US contrast agent microbubbles have a mean diameter of 760 nm with a polydisperity index ...

Multimodal Gold-speckled silica nanoparticles as contrast agents for noninvasive imaging with magnetic resonance imaging and photoacoustic tomography have been prepared in a simple one-pot synthesis using nonionic microemulsions. Magnetic resonance contrast is provided through gadolinium incorporated in the silica matrix, whereas the photoacoustic signal originates from nonuniform, discontinuous gold nanodomains ...

Gadolinium (Gd) based contrast agents (GBCAs) in magnetic resonance imaging (MRI) are used in daily clinical practice and appear safe in most patients; however, nephrogenic systemic fibrosis (NSF) is a recently recognized severe complication associated with GBCAs. It affects primarily patients with renal disease, such as stage 4 or 5 ...

An array of 33 prototype polypeptides was examined as putative contrast agents that can be distinguished from each other based on the chemical exchange saturation transfer (CEST) mechanism. These peptides were chosen based on predictions of the chemical exchange rates of exchangeable amide, amine, and hydroxyl protons that produce this ...

The statement: "An agent harms a victim," depicts a situation that triggers moral emotions. Depending on whether the agent and the victim are the self or someone else, it can lead to four different moral emotions: self-anger ("I harm myself"), guilt ("I harm someone"), other-anger ("someone harms me"), and compassion ...

This article illustrates some innovative applications of liposomes loaded with paramagnetic lanthanide-based complexes in MR molecular imaging field. When a relatively high amount of a Gd(III) chelate is encapsulated in the vesicle, the nanosystem can simultaneously affect both the longitudinal (R(1)) and the transverse (R(2)) relaxation rate of the bulk ...

OBJECTIVE: This article is the first part of a two-part series on MRI safety. In this article, part 1, the topic of MRI contrast agents and nephrogenic systemic fibrosis (NSF) is addressed. CONCLUSION: To prevent incidents and accidents associated with MRI, it is necessary to regularly revisit the safety topics ...

PURPOSE: We evaluated the difference in computed tomography (CT) attenuation values of the intracranial arterial and venous systems among the various contrast injection protocols (higher iodine delivery rate or higher concentration of the agent) on the source images of intracranial three-dimensional CT angiography (3D-CTA) using a multidetector-row CT (MDCT) scanner. ...

Linear polymers of PARACEST agents were prepared by using classical free radical chain polymerization conditions. The Eu3+-polymers exhibited similar intermediate-to-slow water exchange and CEST characteristics as the Eu3+-monomers. This provided an avenue to lower the detection limit of these imaging agents substantially and makes them potentially useful as MRI sensors ...

Nitroxide-based electron paramagnetic resonance (EPR) imaging agents are useful quantitative probes of O2 concentration in vivo in real time. Lipophilic, labile alkanoyloxymethyl esters of nitroxides can cross the blood-brain barrier, and after hydrolysis, the corresponding anionic nitroxide is intracellularly entrapped at levels sufficient to permit O2 measurements. The utility of ...

Although neurosarcoidosis seems to occur in only 5% to 10% of patients who have sarcoidosis, it may lead to significant complications. The diagnosis of neurosarcoidosis usually relies on indirect information from imaging and spinal fluid examination. Although MR imaging remains the most sensitive technique for detecting neurologic disease, other tests, ...

OBJECTIVE: We wanted to compare the clinical usefulness of conventional galactography and MR contrast galactography for diagnosing patients with nipple discharge. MATERIALS AND METHODS: Both conventional galactography and MR contrast galactography were performed prospectively in 16 patients. Gadopentate dimeglumine (0.1 ml) was mixed with non-ionic contrast medium (0.9 ml) to ...

Photoacoustic imaging of living subjects offers higher spatial resolution and allows deeper tissues to be imaged compared with most optical imaging techniques. As many diseases do not exhibit a natural photoacoustic contrast, especially in their early stages, it is necessary to administer a photoacoustic contrast agent. A number of contrast ...

In ultrasonic targeted imaging, specially designed encapsulated microbubbles are used, which are capable of selectively adhering to the target site in the body. A challenging problem is to distinguish the echoes from such adherent agents from echoes produced by freely circulating agents. In the present paper, an equation of radial ...

OBJECTIVE: The purpose of this study was to investigate the use of contrast-enhanced ultrasound imaging (CEUS) to detect the first draining lymph node (FDLN) in a swine model and to determine whether the distance from the contrast agent injection site to the FDLN has any affect on the ability to ...

In computed tomography (CT) several contrast media with different iodine concentrations are available. The aim of this study is to prospectively compare contrast media with iodine concentrations of 300, 370 and 400 mg iodine/ml for chest- CT. 300 consecutive patients were prospectively enrolled, under a waiver of the local ethics ...

PURPOSE: We investigated the recently discovered association between gadolinium based magnetic resonance imaging contrast agents and the development of nephrogenic systemic fibrosis in patients with chronic kidney disease or acute kidney injury. MATERIALS AND METHODS: A systematic review of the PubMed database and publicly available patient databases was performed to ...

One hundred and twenty carcasses were sampled to compare different techniques or methods for prediction of lamb carcass composition and value. Four methods that are used at the Norwegian Meat Research Centre, Animalia, were selected. These were the basic EUROP classification, the advanced EUROP classification using carcass shape and length ...

The development of novel macromolecular contrast agents that offer enhanced relaxivity profiles at high magnetic fields have the potential to greatly improve the diagnosis, understanding, and treatment of disease. To this end, we have designed a monodiperse paramagnetic beta-cyclodextrin click cluster decorated with seven paramagnetic arms. A novel alkyne-functionalized diethylenetriaminetetraacetic ...

The purpose of this phase III clinical trial was to compare two different extracellular contrast agents, 1.0 M gadobutrol and 0.5 M gadopentate dimeglumine, for magnetic resonance imaging (MRI) in patients with known or suspected focal renal lesions. Using a multicenter, single-blind, interindividual, randomized study design, both contrast agents were ...

PURPOSE OF REVIEW: To highlight the use of arterial wall imaging to evaluate the impact of therapies that promote high-density lipoproteins. RECENT FINDINGS: High-density lipoproteins possess a number of biological properties, which have a direct impact on the extent and composition of atherosclerosis. Arterial wall imaging has been employed to ...

The contrast effects of three different contrast media preparations (iohexol 180 mgI/ml, iohexol 240 mgI/ml and iotrolan 240 mgI/ml) in conventional and CT myelography were compared. Three beagle dogs were used and the study employed a cross-over method (total of 9) for each contrast media. The result of CT myelography ...

Visualization of the vascular systems of organs or of small animals is important for an assessment of basic physiological conditions, especially in studies that involve genetically manipulated mice. For a detailed morphological analysis of the vascular tree, it is necessary to demonstrate the system in its entirety. In this study, ...

In recent past magnetic nanoparticles have been explored for a number of biomedical applications due to their superparamagnetic moment with high magnetic saturation value. For these biomedical applications, magnetic nanoparticles require being monodispersed so that the individual nanoparticle has almost identical physico-chemical properties for biodistribution, bioelimination and contrast imaging potential. ...

This study aimed to describe the occurrence of Yersinia pestis, Rickettsia rickettsii, Anaplasma phagocytophilum, and ectoparasites in a wild rodent community in the eastern Sierra Nevada. From May to September 2006, rodents were live-trapped, examined for ectoparasites, and blood was collected. All rodents were serologically tested for antibodies to Y. ...

To study contrast-enhanced MRI guided photodynamic therapy with a pegylated bifunctional polymer conjugate containing an MRI contrast agent and a photosensitizer for minimally invasive image-guided cancer treatment. Pegylated and non-pegylated poly-(L-glutamic acid) conjugates containing mesochlorin e6, a photosensitizer, and Gd(III)-DO3A, an MRI contrast agent, were synthesized. The effect of pegylation ...

Although gadolinium has been the dominant paramagnetic metal for MR paramagnetic contrast agents, the recent association of this lanthanide with nephrogenic systemic fibrosis, an untreatable disease, has spawned renewed interest in alternative metals for MR molecular imaging. We have developed a self-assembled, manganese(III)-labeled nanobialys (1), a toroidal-shaped MR theranostic nanoparticle. ...

The metal manganese is a potent magnetic resonance imaging (MRI) contrast agent that is essential in cell biology. Manganese-enhanced magnetic resonance imaging (MEMRI) is providing unique information in an ever-growing number of applications aimed at understanding the anatomy, the integration, and the function of neural circuits both in normal brain ...