Relevant bibliographies by topics / X-ray contrast agent

Academic literature on the topic 'X-ray contrast agent'

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Published: 9 March 2023

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Journal articles on the topic "X-ray contrast agent"

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Geso, M. "Gold nanoparticles: a new X-ray contrast agent." British Journal of Radiology 80, no. 949 (January 2007): 64–65. http://dx.doi.org/10.1259/bjr/28250432.

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Hainfeld, J. F., D. N. Slatkin, T. M. Focella, and H. M. Smilowitz. "Gold nanoparticles: a new X-ray contrast agent." British Journal of Radiology 79, no. 939 (March 2006): 248–53. http://dx.doi.org/10.1259/bjr/13169882.

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Tse, Justin J., P. Joy Dunmore-Buyze, Maria Drangova, and David W. Holdsworth. "Erbium-Based Perfusion Contrast Agent for Small-Animal Microvessel Imaging." Contrast Media & Molecular Imaging 2017 (2017): 1–10. http://dx.doi.org/10.1155/2017/7368384.

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Micro-computed tomography (micro-CT) facilitates the visualization and quantification of contrast-enhanced microvessels within intact tissue specimens, but conventional preclinical vascular contrast agents may be inadequate near dense tissue (such as bone). Typical lead-based contrast agents do not exhibit optimal X-ray absorption properties when used with X-ray tube potentials below 90 kilo-electron volts (keV). We have developed a high-atomic number lanthanide (erbium) contrast agent, with a K-edge at 57.5 keV. This approach optimizes X-ray absorption in the output spectral band of conventional microfocal spot X-ray tubes. Erbium oxide nanoparticles (nominal diameter < 50 nm) suspended in a two-part silicone elastomer produce a perfusable fluid with viscosity of 19.2 mPa-s. Ultrasonic cavitation was used to reduce aggregate sizes to <70 nm. Postmortem intact mice were perfused to investigate the efficacy of contrast agent. The observed vessel contrast was >4000 Hounsfield units, and perfusion of vessels < 10 μm in diameter was demonstrated in kidney glomeruli. The described new contrast agent facilitated the visualization and quantification of vessel density and microarchitecture, even adjacent to dense bone. Erbium’s K-edge makes this contrast agent ideally suited for both single- and dual-energy micro-CT, expanding potential preclinical research applications in models of musculoskeletal, oncological, cardiovascular, and neurovascular diseases.
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Xi, Yan, Rongbiao Tang, Yujie Wang, and Jun Zhao. "Microbubbles as contrast agent for in-line x-ray phase-contrast imaging." Applied Physics Letters 99, no. 1 (July 4, 2011): 011101. http://dx.doi.org/10.1063/1.3607292.

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Ghazanfari, Adibehalsadat, Shanti Marasini, Huan Yue, Son Long Ho, Xu Miao, Mohammad Yaseen Ahmad, Ji Ae Park, et al. "D-Glucuronic Acid-Coated Ultrasmall Bi2O3 Nanoparticles for CT Imaging." Journal of Nanoscience and Nanotechnology 20, no. 8 (August 1, 2020): 4638–42. http://dx.doi.org/10.1166/jnn.2020.17817.

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Ultrasmall Bi2O3 nanoparticles (davg = 1.5 nm) coated with biocompatible and hydrophilic D-glucuronic acid were prepared for the first time through a simple one-step polyol process and their potential as CT contrast agents were investigated by measuring their X-ray attenuation properties. Their observed X-ray attenuation power was stronger than that of a commercial iodine CT contrast agent at the same atomic concentration, as consistent with the magnitudes of atomic X-ray attenuation coefficients (i.e., Bi > I), and much stronger at the same number density. The results indicate that the nanoparticle sample is a potential CT contrast agent.
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Liu, Wei-Hung, Yang-Kao Wang, Chi-Chang Wu, Win-Pin Deng, Kuang-Hsun Lin, Wen-Cheng Lo, and Ching-Li Tseng. "Contrast enhancement of iohexol-cisplatin-gelatin complex under computed tomography imaging." Journal of Polymer Engineering 34, no. 3 (May 1, 2014): 267–71. http://dx.doi.org/10.1515/polyeng-2013-0223.

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Abstract X-ray computed tomography (CT) is one of the most powerful non-invasive diagnostic techniques nowadays. The iodinated molecules used as CT contrast agents in the clinic have short circulation times in the body, which significantly restrict its applications. Furthermore, some patients are hypersensitive to iodine. So, researchers have made tremendous efforts to improve the property of iodine. Besides, cis-diammineplatinum (II) dichloride (cisplatin), a major chemo agent for cancer treatment, possess higher X-ray attenuation coefficient being a CT contrast agent. The incorporation of cisplatin with an iodinated agent could facilitate the quality of CT images and damage cancer cells simultaneously. To reduce toxicity of a contrast agent, polymer matrix, gelatin, was incorporated for avoiding contact with nontarget cells. In this study, we combined the iodine contrast agent, 1,3-N-bis (2,3-dihydroxypropyl)-5-[N-(2,3-dihydroxypropyl)acetamido]-2,4,6-triiodobenzene-1,3-dicarboxamide (iohexol), with cisplatin, and then examined them in a micro CT with different X-ray tube voltages (50 kV, 80 kV, 100 kV) to find optimal scanning conditions for imaging. As expected, iohexol combined with cisplatin enhanced X-ray attenuation and image contrast. The optimal CT image could be acquired at iohexol and cisplatin concentrations of 50 mg/ml and 3 mg/ml, respectively, under 80 kV irradiation. Finally, the iohexol-cisplatin-gelatin solution was then fabricated into nanoparticles of sizes about 240 nm, which may suitable for in vivo delivery.
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Bailat, Claude J., Theron J. Hamilton, Christoph Rose-Petruck, and Gerald J. Diebold. "Acoustic radiation pressure: A “phase contrast” agent for x-ray phase contrast imaging." Applied Physics Letters 85, no. 19 (2004): 4517. http://dx.doi.org/10.1063/1.1818337.

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Barge, Alessandro, Francesca Baricco, Giancarlo Cravotto, Roberta Fretta, and Luciano Lattuada. "Mechanochemistry Applied to the Synthesis of X-ray Contrast Agent." ACS Sustainable Chemistry & Engineering 8, no. 34 (August 17, 2020): 12825–30. http://dx.doi.org/10.1021/acssuschemeng.0c02928.

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Frenzel, Thomas, Marcus Bauser, Markus Berger, Christoph Stephan Hilger, Christa Hegele-Hartung, Gregor Jost, Christian Neis, et al. "Characterization of a Novel Hafnium-Based X-ray Contrast Agent." Investigative Radiology 51, no. 12 (December 2016): 776–85. http://dx.doi.org/10.1097/rli.0000000000000291.

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Saladino, Giovanni M., Nuzhet I. Kilic, Bertha Brodin, Bejan Hamawandi, Idris Yazgan, Hans M. Hertz, and Muhammet S. Toprak. "Carbon Quantum Dots Conjugated Rhodium Nanoparticles as Hybrid Multimodal Contrast Agents." Nanomaterials 11, no. 9 (August 24, 2021): 2165. http://dx.doi.org/10.3390/nano11092165.

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Nanoparticle (NP)-based contrast agents enabling different imaging modalities are sought for non-invasive bio-diagnostics. A hybrid material, combining optical and X-ray fluorescence is presented as a bioimaging contrast agent. Core NPs based on metallic rhodium (Rh) have been demonstrated to be potential X-ray Fluorescence Computed Tomography (XFCT) contrast agents. Microwave-assisted hydrothermal method is used for NP synthesis, yielding large-scale NPs within a significantly short reaction time. Rh NP synthesis is performed by using a custom designed sugar ligand (LODAN), constituting a strong reducing agent in aqueous solution, which yields NPs with primary amines as surface functional groups. The amino groups on Rh NPs are used to directly conjugate excitation-independent nitrogen-doped carbon quantum dots (CQDs), which are synthesized through citrate pyrolysis in ammonia solution. CQDs provided the Rh NPs with optical fluorescence properties and improved their biocompatibility, as demonstrated in vitro by Real-Time Cell Analysis (RTCA) on a macrophage cell line (RAW 264.7). The multimodal characteristics of the hybrid NPs are confirmed with confocal microscopy, and X-ray Fluorescence (XRF) phantom experiments.
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Dissertations / Theses on the topic "X-ray contrast agent"

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Butzer, Jochen Sieghard. "MARS-CT: Biomedical Spectral X-ray Imaging with Medipix." Thesis, University of Canterbury. Physics and Astronomy, 2009. http://hdl.handle.net/10092/3863.

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Computed Tomography is one of the most important image modalities in medical imaging nowadays. Recent developments have led to a new acquisition technique called 'dual-energy', where images are taken with different x-ray spectra. This enables for the first time spectral information in the CT dataset. Our approach was to use an energy resolving detector (Medipix) and investigate its potential in the medical imaging domain. Images are taken in different energy bins. For acquisition of the data, a CT scanner called 'Medipix All Resolution System' (MARS) scanner was constructed. It was upgraded to achieve better image quality as well as faster scan time and a stable operation. In medical imaging, it is important to achieve a high contrast and a good detail recognition at a low dose. Therefore, it is common practice to use contrast agents to highlight certain regions of the body like e.g. the vascular system. But with a broad spectrum acquisition, it is often impossible to distinguish highly absorbing body elements like bones from the contrast agent. We target this problem by a contrast agent study using different energy bins. This so called spectral contrast agent study has been conducted with small animals using the MARS scanner. The data has been processed to create an optimal CT reconstruction. The image enhancement techniques consist of corrections for noisy pixels, intensity fluctuations and eliminating streaks in the sinograms to reduce ring artifacts. In order to evaluate the data, we used two methods of material identification. The material reconstruction method works on projection data and uses a maximum-likelihood estimation to reconstruct images of base materials. The second method, the principal component analysis (PCA), identifies the relevant information from the spectral dataset in a few derived variables that account for most of the variance in the dataset. This resulted in images with enhanced contrast and removed redundancies. It is possible to combine these images in one colour image where anatomical structures are shown in good detail and certain materials show up in different colors. Based on this new information from spectral data, we could show that it is possible to distinguish the spinal bone from contrast agent.
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Pen, Olga Vladimirovna. "Calculation of the effective atomic number for the iodine contrast agent of the varying concentrations." Thesis, Virginia Tech, 2016. http://hdl.handle.net/10919/78149.

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The author discusses the difficulties that arise with the determination of the concentration of the iodinated contrast agents in the blood stream via the traditional gray-scale computer tomography and searches for the new imaging modalities that would provide for better sensitivity. The topic of the energy-discriminative color CT is discussed as a potential solution and its suitability is evaluated by performing the experiments on the contrast materials phantom and the phantom containing the iohexol solutions of varying concentrations on the original CT system assembled by the author. A method of the effective atomic number mapping is discussed as a viable alternative to the traditional attenuation-based tomography. The dependency of the effective atomic number of the compound on the energy of the x-ray beam is a phenomenon well recorded in the literature, yet no formal study exists to correctly predict the effective atomic number for a given compound. An extensive physical model is developed based on the previously presented models and adaptations unique to the task in order to determine the effective atomic numbers for exact energies experimentally. The method is tested on different materials. The resultant effective atomic numbers for the water, oil, and iohexol-water solutions of varying concentrations are presented in the study. The effects of the k-edge on both the linear attenuation curve and the effective atomic number curve are discussed. The possible future venues of the research are presented in the final part of the thesis.
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ZANARDO, MORENO. "OPTIMISATION OF CONTRAST AGENT ADMINISTRATION FOR CT AND MRI." Doctoral thesis, Università degli Studi di Milano, 2020. http://hdl.handle.net/2434/698794.

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During the PhD course my research projects focused mainly on the effectiveness, safety and optimisation of contrast agents in computed tomography (CT) and magnetic resonance imaging (MRI), subdivided into different studies. This doctoral thesis aims at explore the possible optimisation of contrast medium administration protocols in different clinical contexts. In the first section of my thesis, we proposed two studies focused on the optimisation of the practice of iodinated contrast medium (ICM) injection in CT. First, we tried to verify the conditions for a change in the dose calculation to be administered in patients undergoing an abdominal CT. Since decades, it is an established practice to inject a dose of ICM calculated on the patient total body weight (TBW). However, this approach does not consider the different volume of biodistribution among patients with different body mass index (BMI). Indeed, it was demonstrated that the ICM poorly distributes in adipose tissue and obese patients may receive a higher dose than that really needed. We have hypothesized that dosing ICM as based on the lean body weight (LBW) would be a more appropriate approach. We firstly retrospectively calculated an ICM dose based on LBW that was equivalent to the dose based on TBW in terms of liver contrast enhancement (LCE). We found that the injected ICM dose was highly variable, with underweight patients receiving a higher dose than obese patients, as a radiologist-driven compensation effect. Starting from the results obtained from the retrospective study, we conducted a randomized controlled trial based on the dose equivalent between the ICM based on patient TBW and the dose calculated using LBW. The Ethics Committee approved the single-center, double-blinded randomized controlled trial (trial registration NCT03384979). Patients were randomized to LBW-based ICM dose (0.61 gI/kg of lean body weight), or TBW-based ICM dose (0.44 gI/kg of TBW) and these equivalent doses derived from the retrospective study. In conclusion, LBW- and TBW-based ICM doses lead to a similar LCE with no significantly different variation for the LBW group, negating the study hypothesis and highlighting the knowledge gap about factors affecting LCE. The last part of the section I aimed to systematically review contrast-enhanced spectral mammography (CESM) studies, focusing on adopted CESM technique, ICM issues and adverse reactions ICM related. Of 120 retrieved articles, 84 were included, totalling 14,012 patients. Contrast type and concentration was reported in 79/84 studies (94%), with Iohexol 350 mgI/mL mostly used (25/79, 32%), dose and flow rate in 72/84 (86%), with 1.5 mL/kg dose at 3 mL/s in 62/72 studies (86%). Thirty adverse reactions were reported by 14/84 (17%) studies (26 mild, 3 moderate, 1 severe non-fatal) with a pooled rate of 0.82%. Factory-set kVp, contrast 1.5-mL/kg at 3 mL/s, and 120-s acquisition delay were mostly used and only 1 severe adverse reaction was reported. In the second PhD thesis section, I focused on gadolinium-based contrast agent (GBCA) protocol issues. A systematic review was conducted in collaboration with the University College Dublin (Dublin, Ireland) during the six months fellowship and it was regarding GBCA administration protocols used for cardiothoracic applications of time-resolved (TR) magnetic resonance angiography (MRA) sequences. A search of the literature was performed to identify articles utilising TR-MRA sequences, focusing on type of sequence, adopted technical parameters, GBCA issues and acquisition workflow. Of 117 retrieved articles, 16 matched the inclusion criteria and study population ranged from 5 to 185 patients, for a total of 506 patients who underwent cardiothoracic TR-MRA. The administered GBCA was gadobutrol (Gadovist) in 6/16 (38%) articles, gadopentetate dimeglumine (Magnevist) in 5/16 (31%), gadobenate dimeglumine (Multihance) in 2/16 (13%), gadodiamide (Omniscan) in 2/16 (13%), gadofosveset trisodium (AblavarTM) in 1/16 (6%). GBCA showed highly variable doses among studies: fixed amount or based on patient body weight (0.02–0.2 mmol/kg). In conclusions, a consensus on technique for cardiothoracic applications of TR-MRA is still far from reached, mostly due to differences regarding contrast agent type and dose. Further studies are warranted to provide a common standardised acquisition protocol.
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Wallyn, Justine. "Stealth nanoparticles for preclinical X-rays imaging and multimodal X-rays/MRI (magnetic resonance imaging) imaging." Thesis, Strasbourg, 2017. http://www.theses.fr/2017STRAF074.

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L’imagerie biomédicale est aujourd’hui un outil essentiel pour établir un diagnostic grâce à l’observation des tissus et des fluides biologiques. L’usage d’instruments à imagerie combinée avec des produits de contraste est la clé pour réussir à distinguer précisément un tissu ciblé via l’accumulation de produit de contraste dans le tissu. Les deux principaux appareils à imagerie utilisés sont le scanner à rayons X et l’imagerie à résonance magnétique (IRM). Ils sont fréquemment employés en complément de l’un et l’autre. Typiquement, de petites molécules iodées hydrophiles sont utilisées comme produit de contraste pour la radiographie à rayons X tandis que l’IRM implique des matériaux magnétiques tels que des nanoparticules d’oxyde de fer. Dans le cadre de ce projet doctoral, nous avons donc proposé deux nouveaux produits de contraste dont le premier visait à constituer une alternative aux produits iodés dont la rapide élimination et la toxicité rénale forment deux problèmes récurrents et un second produit, cette fois-ci bimodale, afin de faciliter les procédures d’imagerie bimodale. Pour le premier point, des nanoparticules de polymères iodés pour l’imagerie à rayons X ont été formulées et ce, par une technique de nanoprécipitation. Les paramètres de formulation ont été élucidés de telle sorte que les nanoparticules possédaient une distribution de taille adaptée pour l’administration par voie intraveineuse et une teneur en iode suffisante en iode pour contraster sous rayons X. Une étude in vivo a révélé le potentiel du produit de contraste à visualiser distinctement le foie et la rate et ce, tout en ne présentant pas les principaux problèmes des produits iodés commerciaux. La seconde étude a eu pour but de formuler des nano-véhicules lipidiques capables de générer un contraste pour l’imagerie à rayons X et l’IRM de par l’incorporation d’huile iodée et de nanoparticules d’oxyde de fer dans le coeur de nano-émulsions. Ceci avait pour objectif de fournir une plateforme nanoparticulaire bimodale pour réaliser efficacement et rapidement des procédures d’imagerie multimodale. Nous avons réussi à produire un efficace agent de contraste bimodal permettant d’observer distinctement le foie et les reins par IRM et le foie et la rate par imagerie à rayons X. La pharmacocinétique de la substance administrée a ainsi pu être mise en avant grâce à la bimodalité de l’agent. Employer l’IRM a permis de montrer qu’une fraction de la dose injectée était éliminée par voie rénale tandis que l’imagerie à rayons X a confirmé que les deux tissus, foie et rate,étaient passivement ciblés par l’agent de contraste. Ces deux études ont donc fournies de potentielles solutions pour répondre aux besoins en produits pour l’imagerie à rayons X et en formulations facilitant l’imagerie bimodale des tissus mous
Biomedical imaging is nowadays an essential tool to establish a diagnosis by means of observation of tissues and biological fluids. Combination of imaging instrument with contrast enhancers is a key to obtain clear delineation of a desired tissue by accumulation of a contrast agent into this specific target. The two main imagers are the X-ray scanner and the magnetic resonance imaging (MRI).These imagers are frequently used in conjuncture. Typically, small hydrosoluble iodinated molecules are used as contrasting material for radiography whereas MRI involves magnetic materials like iron oxide nanoparticles. In this work, we proposed two novel contrast agents, the first one was aiming to form an alternative to iodinated contrast agents suffering from fast excretion and causing renal toxicity whereas the second one was aiming at providing bimodal contrasting ability to facilitate access to bimodal imaging procedure in clinics. In the first case, iodinated polymeric nanoparticles, serving for preclinical X-ray imaging were formulated by nanoprecipitation technique. Parameters of formulation were elucidated to provide nanoparticles with size distribution suitable for in vivo administration and high iodine content for contrast enhancement. In vivo study revealed the efficacy of our nanoparticles to clearly visualize liver and spleen and limiting current issues associated with marketed radiopaque contrast agents. The second work achieved was aiming at formulating bimodal lipids-based nanocarriers capable of yielding contrast enhancement for X-ray imaging and MRI by combining iodinated oil and iron oxide nanoparticles within a nano-emulsion core. This would provide bimodal nanoparticulate platform to carry out fast and efficient dual modal imaging procedures. In this context we succeeded to generate efficient dual modal contrast agent yielding clear visualization of liver and kidney by MRI and liver and spleen by X-ray imaging. Pharmacokinetic profile was so determined thanks to bimodal imaging. Using MRI allowed to show that kidneys eliminated a fraction of the dose whereas X-ray imaging confirmed that both tissues, liver and spleen, were passively targeted. These two studies proposed solutions limiting current issues of radiopaque contrast agents and novel formulations to facilitate bimodal imaging for soft tissues imaging
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Li, Xiang. "Nano-émulsions radio-opaques iodées pour applications précliniques en imagerie par rayons X." Thesis, Strasbourg, 2012. http://www.theses.fr/2012STRAF041/document.

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La micro-tomodensitométrie à rayons X (dite micro-CT, CT = Computed Tomography), est une technique d’imagerie de haute résolution qui consiste d’une part à mesurer l’absorption des rayons X par les tissus, et d’autre part de reconstruire les images et les structures anatomiques en 3 dimensions par traitement informatique. L’agent de contraste est une substance capable d’améliorer la visibilité des structures d’un organe ou d’un liquide organique in vivo. Ce travail de thèse a eu pour objectif le développement d’agents de contraste iodés sous formes de nano-émulsions pour des applications précliniques en imagerie biomédicale. Nous nous sommes proposés d’étudier d’une part des nano-émulsions iodées afin d’avoir une longue rémanence vasculaire in vivo, une meilleure biocompatibilité et d’autre part de mettre au point une synthèse et une formulation plus simples que celles des agents de contraste nanoparticulaires commercialisés. Trois différentes huiles iodées ont été synthétisées et utilisées comme partie contrastante dans les nano-émulsions. Enfin, les nano-émulsions de l’α-tocophérol iodé nous ont permis d’atteindre l’objectif de cette thèse. Ces nano-émulsions iodées ont montré une très bonne biocompatibilité et combinent à la fois les propriétés d’un agent de contraste à longue rémanence vasculaire et un agent de contraste spécifique du foie
The X-ray microtomography (called mico-CT, CT = Computed Tomography) is a high-resolution X-ray tomography, uses X-rays to create cross-sections of a 3D-object that later can be used to recreate a virtual model without destroying the original model. The contrast agent is a substance used to enhance the contrast of structures or fluids within the body in medical imaging. The purposes of the thesis were the development of iodine-containing nano-emulsion based contrast for preclinical applications in biomedical imaging. We proposed to study blood pool contrast agents based on iodine-containing nano-emulsions and to develop simpler procedure for the preparation of these iodine-containing nano-emulsions. Three different iodinated oils were synthesized and used as the contrasting part in the nano-emulsions. Finally, nano-emulsions of iodinated α-tocopherol have been enabled us to achieve the purpose of the thesis. These iodinated nano-emulsions demonstrated very good biocompatibility and showed prolonged and significant contrast enhancement in both bloodstream and liver tissues
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Brown, Anna Laura. "Bismuth Nanoparticles as Medical X-ray Contrast Agents: Synthesis, Characterization and Applications." PDXScholar, 2013. https://pdxscholar.library.pdx.edu/open_access_etds/1523.

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Bismuth based nanomaterials have recently attracted attention as heavy element X-ray contrast agents because of the high atomic number and predicted biological compatibility of bismuth. Nanoparticle X-ray contrast agents may enable a number of novel medical imaging applications, including blood pool and site-directed imaging. However these hypothetical applications are hindered by lack of suitable synthetic methods for production of imaging agents. This dissertation describes synthesis of a novel class of bismuth nanoparticles that are aqueously stabilized using poly and monosaccharides. These particles are synthesized using highly biologically compatible reagents and are oxidatively stable in water and in moderately basic buffered solutions. Bismuth nanoparticles stabilized by the polysaccharide dextran have a large hydrodynamic radius and a relatively small bismuth nanocrystal core (4% bismuth by volume.) Glucose-capped particles have a much higher ratio of bismuth by volume (>60%), and experimental CT scans of these particle solutions demonstrate higher X-ray contrast versus a current clinically used radiocontrast agent. Additional syntheses of hydrophobic organoamine-capped bismuth nanoparticles by reduction of an iodobismuth cluster, and development of other X-ray contrast materials, such as a radiopaque surgical sponge marker and ink, using bismuth micoparticles produced by a top-down ball milling method, are also described.
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Silvestri, A. "DEVELOPMENT OF GOLD BASED NANO-SYSTEMS FOR BIOMEDICAL APPLICATIONS." Doctoral thesis, Università degli Studi di Milano, 2017. http://hdl.handle.net/2434/482617.

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Gold nanoparticles (Au NPs) always fascinated the scientific community, demonstrating several applications in nano-medicine, due to the peculiar properties of this metal at the nano-metric scale. First of all, gold is characterized by a strong inert nature, resisting to the air oxidation and corrosion. This chemical non-reactivity is correlated to a bio-inert nature of the metal that makes it an outstanding candidate for the development of in vitro and in vivo devices. Despite this great inertness, Au can form stable bonds with sulphur containing compounds, like thiols or disulfides. Exploiting this kind of chemistry is possible to easy and robustly functionalize Au NPs with different types of polymers, bio-molecules or targeting moieties. Moreover, Au NPs possess fascinating optical properties like localized surface plasmon resonance (LSPR), photoluminescence, enhancement of Raman signals and elevated X-rays attenuation. By tuning the Au NPs size, shape, coating, labelling and active targeting it is possible to obtain designed platforms acting as therapeutic, diagnostic or theranostic agents. In the present thesis are investigated three fundamental aspects correlated with the employment of gold nanoparticles in biomedicine. Au NPs, thanks to the high density and atomic number, present an elevated X-ray absorption coefficient. These NPs, if properly functionalized, can act as effective CT contrast agent and can be easily visualized by mean of in vivo micro-CT analysis. Here in is reported a methodology for the synthesis of highly stable and functionalized Au. The presented method allowed us to tune the surface coatings and the morphology of the Au NPs, designing a “one-pot” synthesis of engineered isotropic and anisotropic nanoparticles. The present study is devoted to elucidate the major factors involved in the in vivo biodistribution of PEGylated Au NPs. The effects of NPs structural parameters (eg. charge, shape and dimension) on the circulation time in the blood pool were analysed. From this study, we derived interesting information, generally applicable to the design of different types nano-structured contrast agents. Furthermore, other two fundamental topics involved in the design of effective nano-structured contrast agents has been investigate: the nanoparticles renal clearance and the active targeting toward inflamed tissues. Moreover, in the present thesis is investigated the interaction of surface functionalized Au NPs with the biological matter. When nanoparticles come in contact with biological materials, bio-molecules are adsorbed on their surface. This phenomenon causes a modification the identity of the systems and an uncontrolled aggregation of the NPs. The investigation of this phenomenon is fundamental to understand both the intracellular dynamics and the physiological behaviour of the nanoparticles. It is essential to consider these factors in the design of nano-systems effectively applicable in the biomedical field. In particular, in the present study, Fluorescence Correlation Spectroscopy (FCS) has been exploited to acquire information on the diffusion times of surface functionalized Au NPs, both in protein solution and in living cells. In the last chapter is investigated a more technical issue, related to the nanoparticles synthesis. In order to think to a reliable application of the nanotechnologies in the biomedical field, innovative synthetic procedure needs to be identified, to ensure a scale up and higher reproducibility of the production. A fluidic manufacturing method for the production of structurally controlled Au NPs was developed. Fluidic chemistry is a promising technology that can address to the scale up and reproducibility issues that affect the nano-materials production. The presented manufacturing method demonstrated to be strongly versatile, allowing the one-pot production of nano-materials with controlled shape, and engineered surface, readily applicable in a vast number of fields.
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Hallouard, François. "Formulation de nano-particules iodées comme agents de contraste a longue rémanence vasculaire pour tomodensitométrie." Thesis, Lyon 1, 2012. http://www.theses.fr/2012LYO10307.

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L’objectif de cette thèse est de réaliser un agent de contraste vasculaire pour tomodensitométrie utilisable en préclinique. En collaboration avec le laboratoire de biogalénique de Strasbourg, ce travail a permis d’obtenir des nano-émulsions iodées produites par diffusion spontanée de surfactif et des nanoparticules iodées produites par ”émulsion - diffusion de solvant”, comme agent de contraste vasculaire. Ces émulsions et particules polymériques présentent en effet, un temps de rémanence vasculaire de plusieurs heures, un pouvoir contrastant suffisant pour un usage en tomodensitométrie (compris entre 170 et 400 HU), la possibilité de les administrer par intraveineuse et une stabilité de plusieurs mois. Les nano-émulsions, notamment celles produites à partir de Lipiodol®, sont les plus prometteuses comme agents de contraste vasculaire de par leur forte radiopacité (475 ± 30 HU) et leur rémanence vasculaire (T1/2 of 4.1 ± 1.10 h). Les nanoparticules iodées à base de PCL présentent un pouvoir contrastant inférieur (168 ± 13 HU) mais elles sont connus pour leur capacité à modifier la libération du principe actif encapsulé. De ce fait même si les agents de contraste de nature lipidique ou ceux inorganiques sont plus performant, elles restent intéressantes pour une visualisation rapide de la distribution du principe actif dans l’organisme. Cette thèse par ailleurs, apporte plusieurs éléments pour la compréhension de la formulation des nano-émulsions obtenues par diffusion spontanée de surfactif et celle des nanoparticules produites par ”émulsion - diffusion de solvant”. Concernant les nano-émulsions, l’influence de l’iodation des huiles et du surfactif a été étudiée autant sur le plan pharmacotechnique que ceux toxicologique et pharmacocinétique. Concernant les nanoparticules à base de PCL, nous avons montré que l’impact du type d’huile et de l’iodation, des polymères PCL et PCL-mPEG et de diverses méthodes de concentration sur la formulation
The aim of this thesis is to formulate a blood pool contrast agent for preclinical X-ray imaging application. In collaboration with the galenic laboratory of Strasbourg, this work has allowed to obtain iodinated nano-emulsions produced by spontaneous diffusion of surfactant and nano-particles produced by iodine ”emulsion - solvent diffusion” as blood pool contrast agent. These emulsions and polymer particles present indeed a vascular persistence of several hours, a sufficient contrast to be use in computed tomography (between 170 and 400 HU), the ability to be administered intravenous and stability of several months. Nano-emulsions, including those produced from Lipiodol®, are the most promising as blood pool contrast media by their high radiopacity (475 ± 30 HU) and vascular persistence (T1/2 of 4.1 ± 1.10 h). Iodinated nano-particles of PCL have a lower X-ray attenuation (168 ± 13 HU), but they are known for their control release of the encapsulated substances. Therefore even if inorganic or lipidic contrast agents show a better contrast, they remain attractive for rapid visualization of the co-encapsulated substance distribution in the body. This thesis also introduced several features for understanding the formulation of nano-emulsions obtained by spontaneous diffusion of surfactant and the nano-particles produced by ”emulsion - solvent diffusion.”
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Halliwell, Lauren. "Investigation and synthesis of alkyl cyanoacrylates and modification of X-ray contrast agents for incorporation into alkyl cyanoacrylate for use in medical devices." Thesis, University of Warwick, 2013. http://wrap.warwick.ac.uk/57640/.

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The work in this thesis involves the development of a protected transesterification route for the production of novel cyanoacrylate monomers. As well as the modification of iodinated contrast agents to increase their solubility in cyanoacrylate, to enable monitoring of the adhesive within the body for possible use in the treatment of brain aneurysms. Chapter 1 provides an introduction to biological adhesives, in particular alky 2-cyanoacrylates and how they degrade to release formaldehyde. Details into iodinated X-ray contrast agents, their structure, uses and synthesis, as well as the current treatments for brain aneurysms. Chapter 2 focuses on the modification of several iodinated contrast agents in order to increase solubility in ethyl cyanoacrylate. Three existing contrast agents were protected using a variety of different protecting groups and tested for solubility in ethyl cyanoacrylate. Partition coefficients were calculated for the successfully modified compounds. Chapter 3 outlines the development of the anthracene protected route for the synthesis of cyanoacrylate monomers, utilising the Diels- Alder and retro-Diels-Alder reactions of anthracene. This route was subsequently used to synthesis a range of cyanoacrylate monomers. Polymerisation of these monomers gave a range of polymers which were tested to determine their rate of degradation through formaldehyde detection. Chapter 4 further details the first and final step of the anthracene protected route developed in chapter 3. It involved 1H NMR experiments to determine how substitution at the 9 and 10 position of anthracene affects the rate of reaction of the forward and retro-Diels-Alder reaction.
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Kilic, Nüzhet Inci. "Graphene Quantum Dots as Fluorescent and Passivation Agents for Multimodal Bioimaging." Thesis, KTH, Tillämpad fysik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-298302.

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Zero-dimensional graphene (carbon) quantum dots have been drawing attention in bio-related applications since their discovery, especially for their optical properties, chemical stability, and easily modifiable surface.  This thesis focuses on the green synthesis of nitrogen-doped graphene quantum dots (GQDs) for dual-mode bioimaging with X-ray fluorescence (XRF) and optical fluorescence. Both conventional and microwave- (MW-)assisted solvothermal methods were followed to investigate the precursors’ effect on the synthesized GQDs. The MW-assisted method permitted the synthesis of uniform GQDs with an excitation-independent behavior, due to highly controllable reaction conditions. It was demonstrated that the molecular structure of the precursors influenced the optical fluorescence properties of the GQDs. Thus, both blue- (BQDs) and red-emitting (RQDs) GQDs were obtained by selecting specific precursors, leading to emission maxima at 438 and 605 nm under the excitation wavelengths of 390 and 585 nm, respectively.  Amine-functionalized Rh nanoparticles (NPs) were chosen as the X-ray fluorescence (XRF) active core, synthesized via MW-assisted hydrothermal method with a custom designed sugar ligand as the reducing agent. These NPs were conjugated with BQDs using EDC-NHS treatment. The hybrid Rh-GQDs NPs exhibited green emission (520 nm) under 490 nm excitation and led to a reduced cytotoxicity with respect to bare Rh NPs, highlighting the passivation role of the GQDs via the real-time cell analysis (RTCA) assay. The hybrid complex constituted a multimodal bioimaging contrastagent, tested with confocal microscopy (in vitro) and XRF phantom experiments.
Sedan deras upptäckt har nolldimensionella kvantprickar av grafen (kol) uppmärksammats inom biorelaterade applikationer, särskilt för deras optiska egenskaper, kemiska stabilitet och enkelt modifierbara yta. Denna avhandling fokuserar på en grön syntesmetod av kvävedopade grafen-kvantprickar för bimodal bioavbildning med röntgenfluorescens och optisk fluorescens. Både konventionella och mikrovågs-assisterade solvotermiska syntesmetoder användes för att undersöka metodernas effekt på de syntetiserade kvantprickarna. Den mikrovågs-assisterade metoden möjliggjorde syntes av uniforma kvantprickar med exciteringsoberoende egenskaper på grund av mycket kontrollerbara reaktionsförhållanden. Det demonstrerades att den molekylära strukturen hos prekursorerna påverkade de optiska fluorescensegenskaperna hos grafen-kvantprickarna. Genom att välja specifika prekursorer erhölls kvantprickar som emitterar i både blått och rött ljus, motsvarande emissionsmaxima vid 438 respektive 605 nm under excitering vid 390 respektive 585 nm. Amin-funktionaliserade Rh-nanopartiklar valdes som en aktiv kärna för röntgenfluorescens, syntetiserad genom en mikrovågs-assisterad hydrotermisk metod med en specialdesignad sockerligand som reduktionsmedel. Dessa nanopartiklar konjugerades med blåemitterande kvantprickar genom EDC-NHS-behandling. De hybrida nanopartiklarna uppvisade grön emission (520 nm) under 490 nm excitation och ledde till en minskad cytotoxicitet uppmätt genom cellanalys i realtid (RTCA) jämfört med endast Rh-nanopartiklar, vilket framhävde passiveringsrollen som kvantprickarna spelar. Hybridkomplexet utgjorde ett multimodalt kontrastmedel för bioavbildning, vilket demonstrerades med konfokalmikroskopi (in vitro) och fantomexperiment med röntgenfluorescens.
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Books on the topic "X-ray contrast agent"

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Werner, Krause, and LINK (Online service), eds. Contrast agents II: Optical, ultrasound, x-ray and radiopharmaceutical imaging. Berlin: Springer-Verlag, 2002.

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Haen, Christoph de. X-Ray Contrast Agent Technology. Taylor & Francis Group, 2019.

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Haen, Christoph de. X-Ray Contrast Agent Technology: A Revolutionary History. Taylor & Francis Group, 2019.

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Haen, Christoph de. X-Ray Contrast Agent Technology: A Revolutionary History. Taylor & Francis Group, 2019.

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X-Ray Contrast Agent Technology: A Revolutionary History. Taylor & Francis Group, 2019.

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Haen, Christoph de. X-Ray Contrast Agent Technology: A Revolutionary History. Taylor & Francis Group, 2019.

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Hughes, Jim. Urology. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780198813170.003.0018.

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Most urology procedures requiring imaging involve removing or bypassing any occlusions to the flow of urine from the kidneys. For demonstrating the urinary tract under X-ray, an iodine-based contrast is used. The radiation dose may be higher in urological procedures than in orthopaedic cases due to the thickness of the patient’s abdomen as compared to the extremities, and the need for longer screening times to demonstrate the flow of the contrast agent. This chapter covers a selection of urology procedures for the removal of ureteric blockages and insertion of stents, covering retrograde pyelograms and antegrade pyelograms (including percutaneous access with lithotripsy). Each procedure includes images that demonstrate the position of the C-arm, patient, and surgical equipment, with accompanying radiographs demonstrating the resulting images.
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Krause, Werner. Contrast Agents II: Optical, Ultrasound, X-Ray and Radiopharmaceutical Imaging. Springer, 2010.

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Blasi, Francesco, and Paolo Tarsia. Therapeutic approach in haemoptysis. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780199600830.003.0127.

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The aim of diagnostic studies in patients with haemoptysis is two-fold—locate the source of bleeding and identify the underlying cause. A chest X-ray may be informative regarding conditions involving the lung parenchyma, pulmonary vasculature, or the heart, but may be normal in 20–40% of cases. A chest CT scan may allow correct localization of the bleeding site in 65–100% of cases. Contrast-enhanced CT scans allow high resolution angiographic studies that may be useful prior to planning bronchial arterial embolization. Bronchoscopy may allow identification of the site of bleeding, identify the underlying cause, help clear the airways from blood clots favouring gas exchange, and be a means to stop the bleeding. Treatment of haemoptysis varies from outpatient management to intensive care unit admittance. Choice of optimal management depends on the intensity of bleeding, degree of respiratory compromise, and severity of underlying cardiorespiratory status. Important steps in the management of patients with massive haemoptysis include resuscitation, airway protection and patient stabilization as the priority, subsequent localization of the site of bleeding, and specific interventions to stop the bleeding and prevent recurrence. Bronchoscopy may be useful in stopping bleeding through use of cold saline lavage, use of topical vasoconstrictive agents, or temporary endobronchial tamponade with a balloon catheter. The procedure of choice in many cases is selective bronchial artery embolization. With this procedure immediate control of bleeding may be obtained in 70–95% of patients, although recurrence has been reported in 10–30% of cases.
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Book chapters on the topic "X-ray contrast agent"

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Liu, Yanlan. "High-Perform Yb-Based Nanoparticulate X-Ray CT Contrast Agent." In Springer Theses, 81–103. Singapore: Springer Singapore, 2017. http://dx.doi.org/10.1007/978-981-10-6168-4_4.

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Kaneko, Ryotaro, Asuka Hatano, and Satoshi Izumi. "X-ray Projection and Fluid Analysis of Contrast Agent Dynamics Through Stenosis." In IFMBE Proceedings, 188–94. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-66169-4_24.

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Karunamuni, Roshan, Ajlan Al Zaki, Anatoliy V. Popov, E. James Delikatny, Sara Gavenonis, Andrew Tsourkas, and Andrew D. A. Maidment. "An Examination of Silver as a Radiographic Contrast Agent in Dual-Energy Breast X-ray Imaging." In Breast Imaging, 418–25. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-31271-7_54.

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Liu, Yanlan. "Hybrid BaYbF5 Nanoparticles: Novel Binary Contrast Agent for High-Resolution in Vivo X-Ray Computed Tomography Angiography." In Springer Theses, 105–20. Singapore: Springer Singapore, 2017. http://dx.doi.org/10.1007/978-981-10-6168-4_5.

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Krause, W. "X-ray Contrast Agents." In Diagnostics of Vascular Diseases, 99–113. Berlin, Heidelberg: Springer Berlin Heidelberg, 1997. http://dx.doi.org/10.1007/978-3-642-60512-3_6.

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Zagoria, Ronald J. "Iodinated contrast agents in neuroradiology." In Advances in X-Ray Contrast, 81–88. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-011-3959-5_11.

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Dawson, Peter. "Contrast agents in interventional radiology." In Advances in X-Ray Contrast, 52–56. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-011-3959-5_7.

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Krause, Werner. "Iodinated X-Ray Contrast Agents." In Iodine Chemistry and Applications, 353–74. Hoboken, NJ: John Wiley & Sons, Inc, 2014. http://dx.doi.org/10.1002/9781118909911.ch19.

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Bettmann, Michael A. "Cardiac use and effects of contrast agents." In Advances in X-Ray Contrast, 46–51. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-011-3959-5_6.

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Wolf, G. L. "Design of X-ray Contrast Agents." In Trends in Contrast Media, 21–30. Berlin, Heidelberg: Springer Berlin Heidelberg, 1999. http://dx.doi.org/10.1007/978-3-642-59814-2_2.

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Conference papers on the topic "X-ray contrast agent"

1

Reichmann, Jakob, Torben Ruhwedel, Wiebke Möbius, and Tim Salditt. "Neodymium acetate as a contrast agent for x-ray phase-contrast tomography." In Developments in X-Ray Tomography XIV, edited by Bert Müller and Ge Wang. SPIE, 2022. http://dx.doi.org/10.1117/12.2627682.

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Lundström, Ulf, Daniel H. Larsson, Per A. C. Takman, Lena Scott, Anna Burvall, and Hans M. Hertz. "X-ray phase contrast angiography using CO2as contrast agent." In SPIE Medical Imaging, edited by Norbert J. Pelc, Robert M. Nishikawa, and Bruce R. Whiting. SPIE, 2012. http://dx.doi.org/10.1117/12.911408.

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Choi, Seongwook, Sinyoung Park, Jung-Joon Min, Changho Lee, and Chulhong Kim. "X-ray induced acoustic computed tomography with a conventional x-ray contrast agent." In Photons Plus Ultrasound: Imaging and Sensing 2021, edited by Alexander A. Oraevsky and Lihong V. Wang. SPIE, 2021. http://dx.doi.org/10.1117/12.2576466.

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Kuo, Willy, Ngoc An Le, Bernhard Spingler, Georg Schulz, Bert Müller, and Vartan Kurtcuoglu. "Tomographic imaging of microvasculature with a purpose-designed, polymeric x-ray contrast agent." In Developments in X-Ray Tomography XIV, edited by Bert Müller and Ge Wang. SPIE, 2022. http://dx.doi.org/10.1117/12.2634303.

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Hoff, Lars, Knut Brabrand, Nicolay Berard Andersen, and Svein Medhus. "Monitoring X-ray contrast agent injections with Doppler ultrasound." In 2008 IEEE Ultrasonics Symposium (IUS). IEEE, 2008. http://dx.doi.org/10.1109/ultsym.2008.0004.

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Lundström, Ulf, Daniel H. Larsson, Ulrica K. Westermark, Anna Burvall, and Hans M. Hertz. "Small-animal microangiography using phase-contrast X-ray imaging and gas as contrast agent." In SPIE Medical Imaging, edited by Bruce R. Whiting and Christoph Hoeschen. SPIE, 2014. http://dx.doi.org/10.1117/12.2043705.

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Heukensfeldt Jansen, Isabelle, Eri Haneda, Bernhard Claus, Jed Pack, Albert Hsiao, Elliot McVeigh, and Bruno De Man. "Estimation of contrast agent concentration from pulsed-mode projections to time contrast-enhanced CT scans." In Seventh International Conference on Image Formation in X-Ray Computed Tomography (ICIFXCT 2022), edited by Joseph Webster Stayman. SPIE, 2022. http://dx.doi.org/10.1117/12.2647156.

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Karunamuni, Roshan, and Andrew D. A. Maidment. "Quantification of a silver contrast agent in dual-energy breast x-ray imaging." In SPIE Medical Imaging, edited by Robert M. Nishikawa and Bruce R. Whiting. SPIE, 2013. http://dx.doi.org/10.1117/12.2008105.

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Tang, Xiangyang, and Yi Yang. "X-ray differential phase contrast and dark-field computed tomography and radiography with microbubbles as contrast agent." In 2013 IEEE 10th International Symposium on Biomedical Imaging (ISBI 2013). IEEE, 2013. http://dx.doi.org/10.1109/isbi.2013.6556757.

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Schäfer, Dirk, Martin Ahrens, Peter Eshuis, and Michael Grass. "Low kV rotational 3D x-ray imaging for improved CNR of iodine contrast agent." In SPIE Medical Imaging, edited by Norbert J. Pelc, Robert M. Nishikawa, and Bruce R. Whiting. SPIE, 2012. http://dx.doi.org/10.1117/12.909909.

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Reports on the topic "X-ray contrast agent"

1

Brown, Anna. Bismuth Nanoparticles as Medical X-ray Contrast Agents: Synthesis, Characterization and Applications. Portland State University Library, January 2000. http://dx.doi.org/10.15760/etd.1522.

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Shomer, Ilan, Ruth E. Stark, Victor Gaba, and James D. Batteas. Understanding the hardening syndrome of potato (Solanum tuberosum L.) tuber tissue to eliminate textural defects in fresh and fresh-peeled/cut products. United States Department of Agriculture, November 2002. http://dx.doi.org/10.32747/2002.7587238.bard.

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The project sought to understand factors and mechanisms involved in the hardening of potato tubers. This syndrome inhibits heat softening due to intercellular adhesion (ICA) strengthening, compromising the marketing of industrially processed potatoes, particularly fresh peeled-cut or frozen tubers. However, ICA strengthening occurs under conditions which are inconsistent with the current ideas that relate it to Ca-pectate following pectin methyl esterase (PME) activity or to formation of rhamnogalacturonan (RG)-II-borate. First, it was necessary to induce strengthening of the middle lamellar complex (MLX) and the ICA as a stress response in some plant parenchyma. As normally this syndrome does not occur uniformly enough to study it, we devised an efficient model in which ICA-strengthening is induced consistently under simulated stress by short-chain, linear, mono-carboxylic acid molecules (OAM), at 65 oC [appendix 1 (Shomer&Kaaber, 2006)]. This rapid strengthening was insufficient for allowing the involved agents assembly to be identifiable; but it enabled us to develop an efficient in vitro system on potato tuber parenchyma slices at 25 ºC for 7 days, whereas unified stress was reliably simulated by OAMs in all the tissue cells. Such consistent ICA-strengthening in vitro was found to be induced according to the unique physicochemical features of each OAM as related to its lipophilicity (Ko/w), pKa, protonated proportion, and carbon chain length by the following parameters: OAM dissociation constant (Kdiss), adsorption affinity constant (KA), number of adsorbed OAMs required for ICA response (cooperativity factor) and the water-induced ICA (ICAwater). Notably, ICA-strengthening is accompanied by cell sap leakage, reflecting cell membrane rupture. In vitro, stress simulation by OAMs at pH<pKa facilitated the consistent assembly of ICAstrengthening agents, which we were able to characterize for the first time at the molecular level within purified insoluble cell wall of ICA-strengthened tissue. (a) With solid-state NMR, we established the chemical structure and covalent binding to cell walls of suberin-like agents associated exclusively with ICA strengthening [appendix 3 (Yu et al., 2006)]; (b) Using proteomics, 8 isoforms of cell wall-bound patatin (a soluble vacuolar 42-kDa protein) were identified exclusively in ICA-strengthened tissue; (c) With light/electron microscopy, ultrastructural characterization, histochemistry and immunolabeling, we co-localized patatin and pectin in the primary cell wall and prominently in the MLX; (d) determination of cell wall composition (pectin, neutral sugars, Ca-pectate) yielded similar results in both controls and ICA-strengthened tissue, implicating factors other than PME activity, Ca2+ or borate ions; (e) X-ray powder diffraction experiments revealed that the cellulose crystallinity in the cell wall is masked by pectin and neutral sugars (mainly galactan), whereas heat or enzymatic pectin degradation exposed the crystalline cellulose structure. Thus, we found that exclusively in ICA-strengthened tissue, heat-resistant pectin is evident in the presence of patatin and suberinlike agents, where the cellulose crystallinity was more hidden than in fresh control tissue. Conclusions: Stress response ICA-strengthening is simulated consistently by OAMs at pH< pKa, although PME and formation of Ca-pectate and RG-II-borate are inhibited. By contrast, at pH>pKa and particularly at pH 7, ICA-strengthening is mostly inhibited, although PME activity and formation of Ca-pectate or RG-II-borate are known to be facilitated. We found that upon stress, vacuolar patatin is released with cell sap leakage, allowing the patatin to associate with the pectin in both the primary cell wall and the MLX. The stress response also includes formation of covalently bound suberin-like polyesters within the insoluble cell wall. The experiments validated the hypotheses, thus led to a novel picture of the structural and molecular alterations responsible for the textural behavior of potato tuber. These findings represent a breakthrough towards understanding of the hardening syndrome, laying the groundwork for potato-handling strategies that assure textural quality of industrially processed particularly in fresh peeled cut tubers, ready-to-prepare and frozen preserved products.
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