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In the evaluation of endolymphatic hydrops (EH) using magnetic resonance (MR) imaging, hybrid of reversed image of positive endolymph signal and native image of perilymph signal multiplied with heavily T2-weighted MR cisternography (HYDROPS-Mi2) imaging with the intravenous administration of a gadolinium-based contrast agent (IV-GBCA) has been utilized. Recently, MR cisternography (MRC) without GBCA has been proposed as a potential alternative method. However, the feasibility of EH evaluation by MRC without GBCA has not been established. The present study aimed to compare HYDROPS-Mi2 imaging with IV-GBCA to MRC without IV-GBCA for the evaluation of EH. In 40 ears of 20 patients with clinically suspected EH, MRC at pre-IV-GBCA and HYDROPS-Mi2 images from 4 h post-IV-GBCA were analyzed. The saccular height on the MRC (SH-MRC) was measured. The percentage of the volume of the endolymphatic space within the whole lymphatic space of the vestibule on the HYDROPS-Mi2 image (%ELvolume-HYD) was measured. The correlation between the SH-MRC and %ELvolume-HYD was calculated. The receiver operating characteristic (ROC) of the SH-MRC and %ELvolume-HYD for the clinical diagnosis of EH was evaluated. The Spearman’s rank correlation coefficient between the SH-MRC and %ELvolume-HYD was 0.102. The areas under the ROC curve were 0.570 for the SH-MRC, and 0.926 for the %ELvolume-HYD. In conclusion, there was no significant correlation between the MRC without IV-GBCA and the HYDOROPS-Mi2 with IV-GBCA in the evaluation of EH., This is an Open Access article distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. To view the details of this license, please visit (http://creativecommons.org/licenses/by-nc-nd/4.0/).

The amygdaloid complex, including the basolateral nucleus (BLA), contributes crucially to emotional and cognitive brain functions, and is a major target of research in both humans and rodents. However, delineating structural amygdala plasticity in both normal and disease-related contexts using neuroimaging has been hampered by the difficulty of unequivocally identifying the boundaries of the BLA. This challenge is a result of the poor contrast between BLA and the surrounding gray matter, including other amygdala nuclei. Here, we describe a novel diffusion tensor imaging (DTI) approach to enhance contrast, enabling the optimal identification of BLA in the rodent brain from magnetic resonance (MR) images. We employed this methodology together with a slice-shifting approach to accurately measure BLA volumes. We then validated the results by direct comparison to both histological and cellular-identity (parvalbumin)-based conventional techniques for defining BLA in the same brains used for MRI. We also confirmed BLA connectivity targets using DTI-based tractography. The novel approach enables the accurate and reliable delineation of BLA. Because this nucleus is involved in and changed by developmental, degenerative and adaptive processes, the instruments provided here should be highly useful to a broad range of neuroimaging studies. Finally, the principles used here are readily applicable to numerous brain regions and across species.

At ambient conditions, rare-earth oxyhydride thin films show reversible photochromism and photoconductivity, while their mechanism and relation are still unclear. In this work, this question is explored with in situ time-resolved measurements of both optical and transport properties of Gd-based oxyhydride thin films. It is found that p-type large polaron conduction is the initial mechanism of charge transport; however, upon photo-darkening, a 104-fold increase of conductivity occurs, and n-type carriers become dominant. Further, photochromism and photoconductivity are shown to originate from a single process, as indicated by the fact that the photoconductivity is exponentially proportional to the increase of optical absorption. This exponential relation, notably, cannot stem from any of the optically absorbing species thought responsible for photochromism and, therefore, suggests that their formation is accompanied by a concerted increase of negative charge carriers in the Gd oxyhydride films., ChemE/Materials for Energy Conversion and Storage, ChemE/O&O groep, QN/Kavli Nanolab Delft, ChemE/Opto-electronic Materials, ChemE/Chemical Engineering

Literární část diplomové práce je zaměřena na kontrastní látky na bázi gadolinia používané pro vyšetření magnetickou rezonancí. Mapuje jejich vývoj, v současnosti používané typy, těchto látek a metody jejich detekce. Dále je věnována způsobům nakládání s těmito odpadními kontrastními látkami, a to jejich zachytávání a degradace (rozklad). Experimentální část je zaměřena na optimalizaci metody mikrovlnného rozkladu kontrastních látek. Optimalizované podmínky jsou použity při zpracování reálných vzorků oplachových vod s obsahem kontrastních látek. Získaná data jsou základem pro sestavení modelů v rámci studie posuzování životního cyklu porovnávající alternativní a konvenční způsob nakládání s kontrastními látkami z hlediska jejich dopadu na životní prostředí., The literature part of the thesis is focused on gadolinium-based contrast agents used for MRI. It maps their development, currently used types of these substances and methods of their detection. Furthermore, the thesis is devoted to the methods of handling these waste contrast agents, namely their capture and degradation (decomposition). The experimental part is focused on the optimization of the microwave decomposition method of contrast agents. The optimized conditions are used in the treatment of real rinse water samples containing contrast agents. The obtained data are the basis for the construction of models in a life cycle assessment study comparing alternative and conventional management of contrast agents in terms of their environmental impact., Fakulta chemicko-technologická, Posluchač seznámil komisi s obsahem své diplomové práce a následně zodpověděl dotazy členů komise. Membránové procesy a tlakové procesy, terminologicky nepřesné. Ekonomické porovnání s nanofiltrací. Využití gadolinia. LCA studie - nezahrnuty poplatky za skládky, těžba, uložení. Dusičnan gadolinitý a popílek. Podíl odpadních látek., Dokončená práce s úspěšnou obhajobou

In the evaluation of endolymphatic hydrops (EH) using magnetic resonance (MR) imaging, hybrid of reversed image of positive endolymph signal and native image of perilymph signal multiplied with heavily T2-weighted MR cisternography (HYDROPS-Mi2) imaging with the intravenous administration of a gadolinium-based contrast agent (IV-GBCA) has been utilized. Recently, MR cisternography (MRC) without GBCA has been proposed as a potential alternative method. However, the feasibility of EH evaluation by MRC without GBCA has not been established. The present study aimed to compare HYDROPS-Mi2 imaging with IV-GBCA to MRC without IV-GBCA for the evaluation of EH. In 40 ears of 20 patients with clinically suspected EH, MRC at pre-IV-GBCA and HYDROPS-Mi2 images from 4 h post-IV-GBCA were analyzed. The saccular height on the MRC (SH-MRC) was measured. The percentage of the volume of the endolymphatic space within the whole lymphatic space of the vestibule on the HYDROPS-Mi2 image (%ELvolume-HYD) was measured. The correlation between the SH-MRC and %ELvolume-HYD was calculated. The receiver operating characteristic (ROC) of the SH-MRC and %ELvolume-HYD for the clinical diagnosis of EH was evaluated. The Spearman’s rank correlation coefficient between the SH-MRC and %ELvolume-HYD was 0.102. The areas under the ROC curve were 0.570 for the SH-MRC, and 0.926 for the %ELvolume-HYD. In conclusion, there was no significant correlation between the MRC without IV-GBCA and the HYDOROPS-Mi2 with IV-GBCA in the evaluation of EH., This is an Open Access article distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. To view the details of this license, please visit (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Conventional x-ray sources for medical imaging utilize bremsstrahlung radiation. These sources generate large bandwidth (BW) x-ray spectra with large fractions of photons that impart a dose, but do not contribute to image production. X-ray sources based on laser-Compton scattering can have inherently small energy BWs and can be tuned to low dose-imparting energies, allowing them to take advantage of atomic K-edge contrast enhancement. This paper investigates the use of gadolinium-based K-edge subtraction imaging in the context of mammography using a laser-Compton source through simulations quantifying contrast and dose in such imaging systems as a function of laser-Compton source parameters. Our simulations indicate that a K-edge subtraction image generated with a 0.5% BW (FWHM) laser-Compton x-ray source can obtain an equal contrast to a bremsstrahlung image with only 3% of the dose.

Rare earth element (REE) and Y (REY) concentrations were determined in soft tissues and shells prepared from 9 to 93 years old dog cockles sampled alive from a marine site in NW Brittany, France. The concentrations shown by the different soft tissues and shells are extremely variable ranging from 9.10-5 to 10-1 x PAAS. The mantle is the organ with the highest concentrations, while the feet, the adductor muscles and the digestive glands display the lowest ones. Relative to the masses of the different organs, we show that the shell concentrates more than 85% of the REY contained in an animal, and the mantle, which represents less than 0.5% of the total animal mass (on a dry basis), contains 10% of the total REY. Organs accumulate REY throughout the life of the animal. REY concentrations in soft tissues increase by more than one order of magnitude in 90 years. The shells mirror the REY abundances of the mantle but are slightly less light-REE enriched than the latter. Furthermore, shells as well as feet and adductor muscles show a striking correlation between animal age and Ce/Ce* ratios. Ce/Ce* ratios evolve from 0.8 for animals aged ∼10 years to 1 for the oldest, with most of the variation during the first 25 years, indicating that Ce also accompanies biochemical reactions probably related to the growth or maturity of the animals. Soft tissues also show extremely variable positive Gd anomalies (Gd/Gd*= 1.04 - 1.94) which indicate environmental pollution by Gd based contrast agents (GBCA) used in medical imaging. Anomalies tend to be more important for organs poor in REY (like muscles and digestive glands). Low excesses of Gd, on the order of 1-3 ng/g (on a dry basis), account for these anomalies. There is no correlation between the age of the animals and the amount of anthropogenic Gd or Gd/Gd* ratios suggesting that GBCAs do not accumulate in the bivalve body on a long-term basis.

In der Arbeit wurden die zwei ternären Oxide GdScO3 und AlTiOx strukturell und elektrisch charakterisiert und in laterale AlGaN/GaN-MISHEMTs integriert. GdScO3 wächst hexagonal und epitaktisch bei einer Abscheidung mittels PLD bei 700°C auf einer AlGaN/GaN Heterostruktur auf. Die demonstrierten MISHEMTs zeigen einen deutlich verringerten Gate-Leckstrom. Zeit- und beleuchtungsabhängige Drain-Strom Messungen im ausgeschaltetem Transistor weisen allerdings auf photoinduzierte Trapzustände mit langer Lebensdauer im Oxid hin, die den Drain-Leckstrom limitieren. Die AlTiOx Mischoxide wurden mittels ALD abgeschieden. Dabei wurde die Stöchiometrie über das Zyklenverhältnis zwischen Al2O3 und TiO2 variiert. Es konnte gezeigt werden, dass der Brechungsindex, die Permittivität, die Bandlücke und das Bandalignment zum GaN über die Stöchiometrie eingestellt werden können. Durch die Implementierung eines high-k last Prozesses konnten schaltbare MISHEMTs prozessiert werden. Durch die Simulation der Bandstruktur konnten die Einsatzspannungsverschiebung und ein Maximum des Drain-Stroms im ausgeschaltetem Zustand über die Ermittlung der Barrierendicke für Elektronen erklärt werden. Für eine Passivierung mit TiO2 wurde ein um 2,5 Größenordnungen reduzierter Drain-Leckstrom bei gleichzeitig nur minimal verschobener Einsatzspannung gemessen.:Inhaltsverzeichnis 1 Einleitung 7 2 Grundlagen 9 2.1 Der III-V Halbleiter Galiumnitrid . . . . . . . . . . . . . . . . . . . . . 9 2.2 Der Hetero-Feldeffekttransisor . . . . . . . . . . . . . . . . . . . . . . . 10 2.3 Performance Einschränkungen am unpassivierten HFET . . . . . . . . 14 2.4 Gatedielektrika für MISHEMTs . . . . . . . . . . . . . . . . . . . . . . 17 2.4.1 Verwendete Dielektrika . . . . . . . . . . . . . . . . . . . . . . . 19 2.4.2 Limitationen in MISHEMTs . . . . . . . . . . . . . . . . . . . . 23 2.5 Atomlagenabscheidung . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 2.5.1 Der ALD-Prozess . . . . . . . . . . . . . . . .

Cardiac magnetic resonance imaging and angiography have a crucial role in the diagnostic evaluation and follow up of pediatric and adult patients with congenital heart disease. Although much of the information required of advanced imaging studies can be provided by standard gadolinium-enhanced magnetic resonance imaging, the limitations of precise bolus timing, long scan duration, complex imaging protocols, and the need to image small structures limit more widespread use of this modality. Recent experience with off-label diagnostic use of ferumoxytol has helped to mitigate some of these barriers. Approved by the U.S. FDA for intravenous treatment of anemia, ferumoxytol is an ultrasmall superparamagnetic iron oxide nanoparticle that has a long blood pool residence time and high relaxivity. Once metabolized by macrophages, the iron core is incorporated into the reticuloendothelial system. In this work, we aim to summarize the evolution of ferumoxytol-enhanced cardiovascular magnetic resonance imaging and angiography and highlight its many applications for congenital heart disease.

In der Arbeit wurden die zwei ternären Oxide GdScO3 und AlTiOx strukturell und elektrisch charakterisiert und in laterale AlGaN/GaN-MISHEMTs integriert. GdScO3 wächst hexagonal und epitaktisch bei einer Abscheidung mittels PLD bei 700°C auf einer AlGaN/GaN Heterostruktur auf. Die demonstrierten MISHEMTs zeigen einen deutlich verringerten Gate-Leckstrom. Zeit- und beleuchtungsabhängige Drain-Strom Messungen im ausgeschaltetem Transistor weisen allerdings auf photoinduzierte Trapzustände mit langer Lebensdauer im Oxid hin, die den Drain-Leckstrom limitieren. Die AlTiOx Mischoxide wurden mittels ALD abgeschieden. Dabei wurde die Stöchiometrie über das Zyklenverhältnis zwischen Al2O3 und TiO2 variiert. Es konnte gezeigt werden, dass der Brechungsindex, die Permittivität, die Bandlücke und das Bandalignment zum GaN über die Stöchiometrie eingestellt werden können. Durch die Implementierung eines high-k last Prozesses konnten schaltbare MISHEMTs prozessiert werden. Durch die Simulation der Bandstruktur konnten die Einsatzspannungsverschiebung und ein Maximum des Drain-Stroms im ausgeschaltetem Zustand über die Ermittlung der Barrierendicke für Elektronen erklärt werden. Für eine Passivierung mit TiO2 wurde ein um 2,5 Größenordnungen reduzierter Drain-Leckstrom bei gleichzeitig nur minimal verschobener Einsatzspannung gemessen.:Inhaltsverzeichnis 1 Einleitung 7 2 Grundlagen 9 2.1 Der III-V Halbleiter Galiumnitrid . . . . . . . . . . . . . . . . . . . . . 9 2.2 Der Hetero-Feldeffekttransisor . . . . . . . . . . . . . . . . . . . . . . . 10 2.3 Performance Einschränkungen am unpassivierten HFET . . . . . . . . 14 2.4 Gatedielektrika für MISHEMTs . . . . . . . . . . . . . . . . . . . . . . 17 2.4.1 Verwendete Dielektrika . . . . . . . . . . . . . . . . . . . . . . . 19 2.4.2 Limitationen in MISHEMTs . . . . . . . . . . . . . . . . . . . . 23 2.5 Atomlagenabscheidung . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 2.5.1 Der ALD-Prozess . . . . . . . . . . . . . . . .

Gadolinium (Gd) is one of the rare-earth elements. The properties of its trivalent cation (Gd3+) make it suitable to serve as the central ion in chelates administered intravenously to patients as a contrast agent in magnetic resonance imaging. Such Gd-chelates have been used for more than thirty years. During the past decades, knowledge has increased about potential harmful effects of Gd-chelates in patients with severe renal dysfunction. In such patients, there is a risk for a potentially disabling and lethal disease, nephrogenic systemic fibrosis. Restricting the use of Gd-chelates in persons with severely impaired renal function has decreased the occurrence of this toxic effect in the last decade. There has also been an increasing awareness of Gd-retention in the body, even in patients without renal dysfunction. The cumulative number of doses given, and the chemical structure of the chelate given, are factors of importance for retention in tissues. This review describes the chemical properties of Gd and its medically used chelates, as well as its toxicity and potential side effects related to injection of Gd-chelates.

Multifrequency electron paramagnetic resonance spectroscopy on oriented single crystals of magnetically dilute Gd(III) ions in Gd0.004Y0.996(trensal) is used to determine the Hamiltonian parameters of the ground (8)S(7/2 )term and its phase memory time, T-m, characterizing its coherent spin dynamics. The vanishing orbital angular momentum of the S-8(7/2) term makes it relatively insensitive to spin-lattice relaxation mediated by magnetoelastic coupling and leads to a T-m of 12 mu s at 3 K, which is not limited by spin-lattice relaxation.

Objectives To assess clinical and cardiac magnetic resonance (CMR) imaging features of patients with peri-myocarditis following Coronavirus Disease 2019 (COVID-19) vaccination. Methods We retrospectively collected a case series of 27 patients who underwent CMR in the clinical suspect of heart inflammation following COVID-19 vaccination, from 16 large tertiary centers. Our patient's cohort was relatively young (36.6 +/- 16.8 years), predominately included males (n = 25/27) with few comorbidities and covered a catchment area of approximately 8 million vaccinated patients. Results CMR revealed typical mid-subepicardial non-ischemic late gadolinium enhancement (LGE) in 23 cases and matched positively with CMR T2 criteria of myocarditis. In 7 cases, typical hallmarks of acute pericarditis were present. Short-term follow-up (median = 20 days) from presentation was uneventful for 25/27 patients and unavailable in two cases. Conclusions While establishing a causal relationship between peri-myocardial inflammation and vaccine administration can be challenging, our clinical experience suggests that CMR should be performed for diagnosis confirmation and to drive clinical decision-making and follow-up.

No abstract available

Accurate scar assessment is crucial in cardiac resynchronization therapy (CRT) candidates, since its presence is a negative predictor for CRT response. Therefore, we assessed the performance of different PET parameters to detect scar in CRT candidates. Twenty-nine CRT candidates underwent 18F-fluorodeoxyglucose (18F-FDG)-PET/computed tomography (CT), resting 13N-NH3-PET/CT and cardiac magnetic resonance (CMR) prior to CRT implantation. Segmental 18F-FDG uptake, late 13N-NH3 uptake and absolute myocardial blood flow (MBF) were evaluated for scar detection using late gadolinium enhancement (LGE) CMR as reference. A receiver operator characteristic (ROC) area under the curve (AUC) ≥0.8 indicated a good accuracy of the methods evaluated. Scar was present in 111 of 464 segments. None of the approaches could reliably identify segments with nontransmural scar, except for 18F-FDG uptake in the lateral wall (AUC 0.83). Segmental transmural scars could be detected with all methods (AUC ≥ 0.8), except for septal 18F-FDG uptake and MBF in the inferior wall (AUC < 0.8). Late 13N-NH3 uptake was the best parameter for transmural scar detection, independent of its location, with a sensitivity of 80% and specificity of 92% using a cutoff of 66% of the maximum tracer activity. Late 13N-NH3 uptake is superior to 13N-NH3 MBF and 18F-FDG in detecting transmural scar, independently of its location. However, none of the tested PET parameters was able to accurately detect nontransmural scar.

Magnetic refrigeration systems are promising cooling solutions that employ the active magnetic regenerator refrigeration cycle to achieve practical temperature spans and environmental benefits. The hydraulic system that ensures a continuous flow of the heat transfer fluid through the system with a reciprocating flow in each regenerator bed is critical to the performance of the refrigeration cycle. Hence, we investigate the characteristics of the parallel flow circuit of a rotary active magnetic regenerator system, which consists of thirteen trapezoid-shaped regenerators, each filled with 295 g of gadolinium spheres. Fluid flow is controlled via electrically actuated solenoid valves (both piloted and direct-acting) connected to the regenerator hot side. By varying the percentage of opening of the control valves, different blow fractions (or fluid flow waveforms) could be investigated. The objective of the study is twofold: (i) assess whether flow imbalances of the heat transfer fluid exist in the cold-to-hot blow (cold blow) and hot-to-cold blow (hot blow) directions, and (ii) determine whether there is an optimal value of the blow fraction both to maximize the cooling performance and realize a rapid temperature pulldown. Flow resistance measurements demonstrate a symmetric flow circuit design and resistances that are similar in the cold and hot blow directions. Moreover, for the studied temperature spans of 6 K and 16 K, the best blow fraction was found to be about 41.6 %. For instance, at a 16 K span, a utilization of 0.32, and at 1.4 Hz, increasing the fluid blow fraction from 25.0 to 41.6 % enhanced the cooling capacity and second-law efficiency from 70 to 330 W and from 2.6 to 17.4 %, respectively. In turn, lower blow fractions favored a more rapid temperature pulldown. The magnetocaloric system was about 30 % faster in establishing approximately 14 K temperature span when the blow fraction was reduced from 41.6 to 30.6 %. Hence, magnetic refrigeration systems c

Colony-stimulating factor 1 receptor (CSF1R)-related leukoencephalopathy is a rare but fatal microgliopathy. The diagnosis is often delayed due to multifaceted symptoms that can mimic several other neurological disorders. Imaging provides diagnostic clues that help identify cases. The objective of this study was to integrate the literature on neuroimaging phenotypes of CSF1R-related leukoencephalopathy. A systematic review and meta-analysis were performed for neuroimaging findings of CSF1R-related leukoencephalopathy via PubMed, Web of Science, and Embase on 25 August 2021. The search included cases with confirmed CSF1R mutations reported under the previous terms hereditary diffuse leukoencephalopathy with spheroids, pigmentary orthochromatic leukodystrophy, and adult-onset leukoencephalopathy with axonal spheroids and pigmented glia. In 78 studies providing neuroimaging data, 195 cases were identified carrying CSF1R mutations in 14 exons and five introns. Women had a statistically significant earlier age of onset (p = 0.041, 40 vs 43 years). Mean delay between symptom onset and neuroimaging was 2.3 years. Main magnetic resonance imaging (MRI) findings were frontoparietal white matter lesions, callosal thinning, and foci of restricted diffusion. The hallmark computed tomography (CT) finding was white matter calcifications. Widespread cerebral hypometabolism and hypoperfusion were reported using positron emission tomography and single-photon emission computed tomography. In conclusion, CSF1R-related leukoencephalopathy is associated with progressive white matter lesions and brain atrophy that can resemble other neurodegenerative/-inflammatory disorders. However, long-lasting diffusion restriction and parenchymal calcifications are more specific findings that can aid the differential diagnosis. Native brain CT and brain MRI (with and without a contrast agent) are recommended with proposed protocols and pictorial examples are provided., QC 20220610

Gadolinium (Gd) is one of the rare-earth elements. The properties of its trivalent cation (Gd3+) make it suitable to serve as the central ion in chelates administered intravenously to patients as a contrast agent in magnetic resonance imaging. Such Gd-chelates have been used for more than thirty years. During the past decades, knowledge has increased about potential harmful effects of Gd-chelates in patients with severe renal dysfunction. In such patients, there is a risk for a potentially disabling and lethal disease, nephrogenic systemic fibrosis. Restricting the use of Gd-chelates in persons with severely impaired renal function has decreased the occurrence of this toxic effect in the last decade. There has also been an increasing awareness of Gd-retention in the body, even in patients without renal dysfunction. The cumulative number of doses given, and the chemical structure of the chelate given, are factors of importance for retention in tissues. This review describes the chemical properties of Gd and its medically used chelates, as well as its toxicity and potential side effects related to injection of Gd-chelates.

Gadolinium (Gd) is one of the rare-earth elements. The properties of its trivalent cation (Gd3+) make it suitable to serve as the central ion in chelates administered intravenously to patients as a contrast agent in magnetic resonance imaging. Such Gd-chelates have been used for more than thirty years. During the past decades, knowledge has increased about potential harmful effects of Gd-chelates in patients with severe renal dysfunction. In such patients, there is a risk for a potentially disabling and lethal disease, nephrogenic systemic fibrosis. Restricting the use of Gd-chelates in persons with severely impaired renal function has decreased the occurrence of this toxic effect in the last decade. There has also been an increasing awareness of Gd-retention in the body, even in patients without renal dysfunction. The cumulative number of doses given, and the chemical structure of the chelate given, are factors of importance for retention in tissues. This review describes the chemical properties of Gd and its medically used chelates, as well as its toxicity and potential side effects related to injection of Gd-chelates.

Gadolinium (Gd) is one of the rare-earth elements. The properties of its trivalent cation (Gd3+) make it suitable to serve as the central ion in chelates administered intravenously to patients as a contrast agent in magnetic resonance imaging. Such Gd-chelates have been used for more than thirty years. During the past decades, knowledge has increased about potential harmful effects of Gd-chelates in patients with severe renal dysfunction. In such patients, there is a risk for a potentially disabling and lethal disease, nephrogenic systemic fibrosis. Restricting the use of Gd-chelates in persons with severely impaired renal function has decreased the occurrence of this toxic effect in the last decade. There has also been an increasing awareness of Gd-retention in the body, even in patients without renal dysfunction. The cumulative number of doses given, and the chemical structure of the chelate given, are factors of importance for retention in tissues. This review describes the chemical properties of Gd and its medically used chelates, as well as its toxicity and potential side effects related to injection of Gd-chelates.

Tato bakalářská práce je zaměřena na vybrané polyaza deriváty, jejich výskyt v životním prostředí a způsoby jejich odstranění z odpadních vod. Jako významný představitel byla zvolena kontrastní látka na bázi gadolinia (Gadovist). Byly ověřené možné způsoby odstraňování této látky z vody pomocí komerčně dostupných sorbentů. Pro vyhodnocení výsledku sorpce byla využita metoda optická emisní spektrometrie s buzením v indukčně vázaném plazmatu (ICP-OES)., This bachelor's thesis is focused on selected polyaza derivatives, their occurrence in the environment and methods of their removal from wastewater. A gadolinium-based contrast agent (Gadovist) was chosen as a significant representative. Possible methods for removing this substance from water using commercially available sorbents have been tested. The inductively coupled plasma optical emission spectrometry (ICP-OES) method was used to evaluate the sorption result., Fakulta chemicko-technologická, Volba sorbčních materiálů, vylučování Gd z těla pacienta, Dokončená práce s úspěšnou obhajobou

Gadolinium (Gd) is one of the rare-earth elements. The properties of its trivalent cation (Gd3+) make it suitable to serve as the central ion in chelates administered intravenously to patients as a contrast agent in magnetic resonance imaging. Such Gd-chelates have been used for more than thirty years. During the past decades, knowledge has increased about potential harmful effects of Gd-chelates in patients with severe renal dysfunction. In such patients, there is a risk for a potentially disabling and lethal disease, nephrogenic systemic fibrosis. Restricting the use of Gd-chelates in persons with severely impaired renal function has decreased the occurrence of this toxic effect in the last decade. There has also been an increasing awareness of Gd-retention in the body, even in patients without renal dysfunction. The cumulative number of doses given, and the chemical structure of the chelate given, are factors of importance for retention in tissues. This review describes the chemical properties of Gd and its medically used chelates, as well as its toxicity and potential side effects related to injection of Gd-chelates.

BackgroundGadofosveset is a gadolinium-based blood pool contrast agent that was approved by the United States Food and Drug Administration in 2008. Its unanticipated withdrawal from production in 2016 created a void in the blood pool agent inventory and highlighted the need for an alternative agent with comparable imaging properties.ObjectiveThe purpose of our study is to compare the diagnostic image quality, vascular contrast-to-noise ratio (CNR) and temporal signal characteristics of gadofosveset trisodium and ferumoxytol at similar molar doses for high-resolution, three-dimensional (3-D) magnetic resonance (MR) venography in children.Materials and methodsThe medical records and imaging data sets of patients who underwent high-resolution 3-D gadofosveset-enhanced MR venography (GE-MRV) or ferumoxytol-enhanced MR venography (FE-MRV) were retrospectively reviewed. Two groups of 20 pediatric patients (age- and weight-matched with one patient common to both groups; age range: 2 days-15 years) who underwent high-resolution 3-D GE-MRV or FE-MRV at similar molar doses were identified and analyzed. Qualitative analysis of image quality and vessel definition was performed by two blinded pediatric radiologists. Interobserver agreement was assessed with the AC1 (first-order agreement coefficient) statistic. Signal-to-noise ratio (SNR) and CNR of the inferior vena cava and aorta were measured in the steady-state venous phase. Medical records were retrospectively reviewed for any adverse reactions associated with either contrast agent.ResultsMeasured SNR and CNR of the inferior vena cava were higher for FE-MRV than GE-MRV (P = 0.034 and P < 0.001, respectively). The overall image quality score and individual vessel scores of FE-MRV were equal to or greater than GE-MRV (P = 0.084), with good interobserver agreement (AC1 = 0.657). The venous signal on FE-MRV was stable over the longest interval measured (1 h, 13 min and 46 s), whereas venous signal on

Nanometric size Ca1-xGdxMnO3 (x = 0.05, 0.1, 0.15, 0.2) powder particles with perovskite-type structure were obtained by applying a modified glycine-nitrate procedure. [1, 2] All samples were investigated by X-ray diffraction (XRD), Infrared (IR) spectroscopy and EPR (electron paramagnetic resonance) measurements. In the perovskites with space group Pnma, octahedral tilting is most common and it is of great interest for geologists and materials science. It was experimentally observed how the amount of gadolinium dopants affects on the Mn-O bonds angles and distances, MnO6 octahedral tilting, the deformation due to the presence of Jahn-Teller distortion around the Mn3+ cation and relation between the structural and magnetic behavior. [3] The infrared reflection spectra of Ca1-xGdxMnO3 samples confirmed XRD results that Ca1-xGdxMnO3 nanopowders are of Pnma-1 structure and that the octahedral tilting is increased with Gd doping. The EPR spectra are in agreement with the expectation that EPR linewidth depend of Mn-O-Mn angle and that small octahedral tilting brought only a small change of the EPR linewidth.

We present the experimental results for a rotary magnetocaloric prototype, which uses the concept of active magnetic regeneration, presenting an alternative to conventional vapor compression cooling systems. Thirteen packed-bed regenerators subjected to a rotating two-pole permanent magnet with a maximum magnetic field of 1.44 T are implemented. It is the first performance assessment of the device with gadolinium spheres as the magnetocaloric refrigerant and water mixed with commercial ethylene glycol as the heat transfer fluid. The importance of various operating parameters, such as fluid flow rate, cycle frequency, cold and hot reservoir temperatures, and blow fraction on the system performance is reported. The cycle frequency and utilization factor ranged from 0.5 to 1.7 Hz and 0.25 to 0.50, respectively. Operating at near room temperature and employing 3.83 kg of gadolinium, the device produced cooling powers exceeding 800 W at a coefficient of performance of 4 or higher over a temperature span of above 10 K at 1.4 Hz. It was also shown that variations in the flow resistance between the beds could significantly limit the system performance, and a method to correct those is presented. The performance metrics presented compare well with those of currently existing magnetocaloric devices. Such a device could achieve efficiencies as high as conventional vapor compression systems without the use of refrigerants that have high global warming potential.

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BACKGROUND: Neonates and young children require efficacious magnetic resonance imaging (MRI) examinations but are potentially more susceptible to the short- and long-term adverse effects of gadolinium-based contrast agents due to the immaturity of their body functions. OBJECTIVE: To evaluate the acute safety and diagnostic efficacy of gadoteridol (ProHance) for contrast-enhanced MRI of the central nervous system (CNS) in children ≤2 years of age. MATERIALS AND METHODS: One hundred twenty-five children ≤2 years old (including 57 children <6 months old) who underwent contrast-enhanced MRI of the CNS with gadoteridol at 0.1 mmol/kg body weight were retrospectively enrolled at five imaging centers. Safety data were assessed for acute/subacute adverse events in the 48 h following gadoteridol administration and, when available, vital signs, electrocardiogram (ECG) and clinical laboratory values obtained from blood samples taken from 48 h before until 48 h following the MRI exam. The efficacy of gadoteridol-enhanced MRI compared to unenhanced MRI for disease diagnosis was evaluated prospectively by three blinded, unaffiliated readers. RESULTS: Thirteen changes of laboratory values (11 mild, 1 moderate, 1 unspecified) were reported as adverse events in 7 (5.6%) patients. A relationship to gadoteridol was deemed possible though doubtful for two of these adverse events in two patients (1.6%). There were no clinical adverse events, no serious adverse events and no clinically meaningful changes in vital signs or ECG recordings. Accurate differentiation of tumor from non-neoplastic disease, and exact matching of specific MRI-determined diagnoses with on-site final diagnoses, was achieved in significantly more patients by each reader following the evaluation of combined pre- and post-contrast images compared to pre-contrast images alone (84.6-88.0% vs. 70.9-76.9%; P≤0.006 and 67.5-79.5% vs. 47.0-66.7%; P≤0.011, respectively). CONCLUSION: Gadoteridol at

The reactivity of a fuel assembly including burnable absorbers can become the largest at low fuel burnup, so the accuracy of reactivity calculations for such systems is important. To investigate this issue, the impact of gadolinium isotopes' nuclear data on neutron multiplication factor k is quantified. Sensitivities of k to nuclear data are calculated from 0 to 20 GWD/t for a BWR 3 x 3 multicell model. Sensitivity to gadolinium-157 (n, gamma) cross section becomes the largest at the zero burnup. Sensitivity to gadolinium-155 (n, gamma) cross sections takes the two largest values and the second one is observed around fuel burnup where the reactivity reaches its peak. Sensitivities are also calculated for BWR and PWR assemblies, and similar trends are observed. Finally, nuclear data-induced uncertainties of k are quantified. Gadolinium-157 contribution is the largest at zero burnup, and gadolinium-155 contribution is relatively important around fuel burnup corresponding to the reactivity peak.

BackgroundClinical management of boys with Duchenne muscular dystrophy (DMD) relies on in-depth understanding of cardiac involvement, but right ventricular (RV) structural and functional remodeling remains understudied.PurposeTo evaluate several analysis methods and identify the most reliable one to measure RV pre- and postcontrast T1 (RV-T1) and to characterize myocardial remodeling in the RV of boys with DMD.Study typeProspective.PopulationBoys with DMD (N = 27) and age-/sex-matched healthy controls (N = 17) from two sites.Field strength/sequence3.0 T using balanced steady state free precession, motion-corrected phase sensitive inversion recovery and modified Look-Locker inversion recovery sequences.AssessmentBiventricular mass (Mi), end-diastolic volume (EDVi) and ejection fraction (EF) assessment, tricuspid annular excursion (TAE), late gadolinium enhancement (LGE), pre- and postcontrast myocardial T1 maps. The RV-T1 reliability was assessed by three observers in four different RV regions of interest (ROI) using intraclass correlation (ICC).Statistical testsThe Wilcoxon rank sum test was used to compare RV-T1 differences between DMD boys with negative LGE(-) or positive LGE(+) and healthy controls. Additionally, correlation of precontrast RV-T1 with functional measures was performed. A P-value <0.05 was considered statistically significant.ResultsA 1-pixel thick RV circumferential ROI proved most reliable (ICC > 0.91) for assessing RV-T1. Precontrast RV-T1 was significantly higher in boys with DMD compared to controls. Both LGE(-) and LGE(+) boys had significantly elevated precontrast RV-T1 compared to controls (1543 [1489-1597] msec and 1550 [1402-1699] msec vs. 1436 [1399-1473] msec, respectively). Compared to healthy controls, boys with DMD had preserved RVEF (51.8 [9.9]% vs. 54.2 [7.2]%, P = 0.31) and significantly reduced RVMi (29.8 [9.7] g vs. 48.0 [15.7] g), RVEDVi (69.8 [29.7] mL/m2 vs. 89.1 [21.9]&nbsp

The reactivity of a fuel assembly including burnable absorbers can become the largest at low fuel burnup, so the accuracy of reactivity calculations for such systems is important. To investigate this issue, the impact of gadolinium isotopes' nuclear data on neutron multiplication factor k is quantified. Sensitivities of k to nuclear data are calculated from 0 to 20 GWD/t for a BWR 3 x 3 multicell model. Sensitivity to gadolinium-157 (n, gamma) cross section becomes the largest at the zero burnup. Sensitivity to gadolinium-155 (n, gamma) cross sections takes the two largest values and the second one is observed around fuel burnup where the reactivity reaches its peak. Sensitivities are also calculated for BWR and PWR assemblies, and similar trends are observed. Finally, nuclear data-induced uncertainties of k are quantified. Gadolinium-157 contribution is the largest at zero burnup, and gadolinium-155 contribution is relatively important around fuel burnup corresponding to the reactivity peak.

The reactivity of a fuel assembly including burnable absorbers can become the largest at low fuel burnup, so the accuracy of reactivity calculations for such systems is important. To investigate this issue, the impact of gadolinium isotopes' nuclear data on neutron multiplication factor k is quantified. Sensitivities of k to nuclear data are calculated from 0 to 20 GWD/t for a BWR 3 x 3 multicell model. Sensitivity to gadolinium-157 (n, gamma) cross section becomes the largest at the zero burnup. Sensitivity to gadolinium-155 (n, gamma) cross sections takes the two largest values and the second one is observed around fuel burnup where the reactivity reaches its peak. Sensitivities are also calculated for BWR and PWR assemblies, and similar trends are observed. Finally, nuclear data-induced uncertainties of k are quantified. Gadolinium-157 contribution is the largest at zero burnup, and gadolinium-155 contribution is relatively important around fuel burnup corresponding to the reactivity peak.

To compare reliabilities of assessing synovitis in hand osteoarthritis (OA) using Magnetic Resonance Imaging (MRI) with/without gadolinium (Gd). Three readers scored synovitis on non-enhanced two-dimensional (2D) proton density (PD)-weighted MRI and Gd-enhanced (3D) MRI of hand joints in 20 patients. Inter-reader reliabilities were examined. Reliability was good for Gd-enhanced MRI, but poor for non-enhanced PD-weighted MRI (intraclass correlation coefficient 0.83 and 0.21, respectively). Agreement between the two sequences was poor (weighted kappa 0.18). Gd-enhanced MRI was more reliable than PD-weighted MRI for assessing synovitis. Gd-enhancement, but also resolution and tissue contrast, might have contributed to this.

ObjectiveIt is unknown how patients prioritize gadolinium-based contrast media (GBCM) benefits (detection sensitivity) and risks (reactions, gadolinium retention, cost). The purpose of this study is to measure preferences for properties of GBCM in women at intermediate or high risk of breast cancer undergoing annual screening MRI.MethodsAn institutional reviewed board-approved prospective discrete choice conjoint survey was administered to patients at intermediate or high risk for breast cancer undergoing screening MRI at 4 institutions (July 2018-March 2020). Participants were given 15 tasks and asked to choose which of two hypothetical GBCM they would prefer. GBCMs varied by the following attributes: sensitivity for cancer detection (80-95%), intracranial gadolinium retention (1-100 molecules per 100 million administered), severe allergic-like reaction rate (1-19 per 100,000 administrations), mild allergic-like reaction rate (10-1000 per 100,000 administrations), out-of-pocket cost ($25-$100). Attribute levels were based on published values of existing GBCMs. Hierarchical Bayesian analysis was used to derive attribute "importance." Preference shares were determined by simulation.ResultsResponse (87% [247/284]) and completion (96% [236/247]) rates were excellent. Sensitivity (importance = 44.3%, 95% confidence interval = 42.0-46.7%) was valued more than GBCM-related risks (mild allergic-like reaction risk (19.5%, 17.9-21.1%), severe allergic-like reaction risk (17.0%, 15.8-18.1%), intracranial gadolinium retention (11.6%, 10.5-12.7%), out-of-pocket expense (7.5%, 6.8-8.3%)). Lower income participants placed more importance on cost and less on sensitivity (p < 0.01). A simulator is provided that models GBCM preference shares by GBCM attributes and competition.ConclusionsPatients at intermediate or high risk for breast cancer undergoing MRI screening prioritize cancer detection over GBCM-related risks, and prioritize reaction risks over gadolinium retention.Key po

The  160Gd(p,n)160Tb excitation function was measured between 4-18 MeV using stacked-target activation at Lawrence Berkeley National Laboratory's 88-Inch Cyclotron. Nine copper and eight titanium foils served as proton fluence monitor foils, using the  natCu(p,x)65Zn,  natTi(p,x)48V, and  natTi(p,x)46Sc monitor standards, respectively. Variance minimization using an MCNP v.6.2 model reduced the systematic uncertainties in proton energy and fluence. A priori predictions of the  160Gd(p,n) reaction using ALICE, CoH, EMPIRE, and TALYS, as well as the TENDL database, are compared to the experimentally measured values.

Emerging and promising therapeutic interventions for Duchenne muscular dystrophy (DMD) are confounded by the challenges of quantifying dystrophin. Current approaches have poor precision, require large amounts of tissue, and are difficult to standardize. This paper presents an immuno-mass spectrometry imaging method using gadolinium (Gd)-labeled anti-dystrophin antibodies and laser ablation-inductively coupled plasma-mass spectrometry to simultaneously quantify and localize dystrophin in muscle sections. Gd is quantified as a proxy for the relative expression of dystrophin and was validated in murine and human skeletal muscle sections following k-means clustering segmentation, before application to DMD patients with different gene mutations where dystrophin expression was measured up to 100 µg kg-1 Gd. These results demonstrate that immuno-mass spectrometry imaging is a viable approach for pre-clinical to clinical research in DMD. It rapidly quantified relative dystrophin in single tissue sections, efficiently used valuable patient resources, and may provide information on drug efficacy for clinical translation.

Purpose Low molecular weight iron(III) complex‐based contrast agents (IBCA) including iron(III) trans‐cyclohexane diamine tetraacetic acid [Fe(tCDTA)]− could serve as alternatives to gadolinium‐based contrast agents in MRI. In search for IBCA with enhanced properties, we synthesized derivatives of [Fe(tCDTA)]− and compared their contrast effects. Methods Trans‐cyclohexane diamine tetraacetic acid (tCDTA) was chemically modified in 2 steps: first the monoanhydride of Trans‐cyclohexane diamine tetraacetic acid was generated, and then it was coupled to amines in the second step. After purification, the chelators were analyzed by high‐performance liquid chromatography, mass spectrometry, and NMR spectrometry. The chelators were complexed with iron(III), and the relaxivities of the complexes were measured at 0.94, 1.5, 3, and 7 Tesla. Kinetic stabilities of the complexes were analyzed spectrophotometrically and the redox properties by cyclic voltammetry. Results Using ethylenediamine (en) and trans‐1,4‐diaminocyclohexane, we generated monomers and dimers of tCDTA: en‐tCDTA, en‐tCDTA‐dimer, trans‐1,4‐diaminocyclohexane‐tCDTA, and trans‐1,4‐diaminocyclohexane‐tCDTA‐dimer. The iron(III) complexes of these derivatives had similarly high stabilities as [Fe(tCDTA)]−. The iron(III) complexes of the trans‐1,4‐diaminocyclohexane derivatives had higher T1 relaxivities than [Fe(tCDTA)]− that increased with increasing magnetic field strengths and were highest at 6.8 L·mmol−1·s−1 per molecule for the dimer. Remarkably, the relaxivity of [Fe(en‐tCDTA)]+ had a threefold increase from neutral pH toward pH6. Conclusion Four iron(III) complexes with similar stability in comparison to [Fe(tCDTA)]− were synthesized. The relaxivities of trans‐1,4‐diaminocyclohexane‐tCDTA and trans‐1,4‐diaminocyclohexane‐tCDTA‐dimer complexes were in the same range as gadolinium‐based contrast agents at 3 Tesla. The [Fe(en‐tCDTA)]+ complex is a pH sensor at weakly acidic pH levels, which are typical for vario, DFG, Peer Reviewed, Peer Reviewed

Terbium (Tb) is a promising element for the theranostic approach in nuclear medicine. The new CERN-MEDICIS facility aims for production of its medical radioisotopes to support related R&D projects in biomedicine. The use of laser resonance ionization is essential to provide radioisotopic yields of highest quantity and quality, specifically regarding purity. This paper presents the results of preparation and characterization of a suitable two-step laser resonance ionization process for Tb. By resonance excitation via an auto-ionizing level, the high ionization efficiency of 53% was achieved. To simulate realistic production conditions for Tb radioisotopes, the influence of a surplus of Gd atoms, which is a typical target material for Tb generation, was considered, showing the necessity of radiochemical purification procedures before mass separation. Nevertheless, a 10-fold enhancement of the Tb ion beam using laser resonance ionization was observed even with Gd:Tb atomic ratio of 100:1. © Copyright © 2021 Gadelshin, Formento Cavaier, Haddad, Heinke, Stora, Studer, Weber and Wendt.

In this article, a novel method of simultaneous carborane-and gadolinium-containing compounds as efficient agents for neutron capture therapy (NCT) delivery via magnetic nanocarriers is presented. The presence of both Gd and B increases the efficiency of NCT and using nanocarriers enhances selectivity. These factors make NCT not only efficient, but also safe. Superparamagnetic Fe3O4 nanoparticles were treated with silane and then the polyelectrolytic layer was formed for fur-ther immobilization of NCT agents. Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), energy dispersive X-ray (EDX), ultraviolet–visible (UV-Vis) and Mössbauer spectroscopies, dynamic light scattering (DLS), scanning electron microscopy (SEM), vibrating-sample magnetometry (VSM) were applied for the characterization of the chemical and element composition, structure, mor-phology and magnetic properties of nanocarriers. The cytotoxicity effect was evaluated on different cell lines: BxPC-3, PC-3 MCF-7, HepG2 and L929, human skin fibroblasts as normal cells. average size of nanoparticles is 110 nm; magnetization at 1T and coercivity is 43.1 emu/g and 8.1, respectively; the amount of B is 0.077 mg/g and the amount of Gd is 0.632 mg/g. Successful immobilization of NCT agents, their low cytotoxicity against normal cells and selective cytotoxicity against cancer cells as well as the superparamagnetic properties of nanocarriers were confirmed by analyses above. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

The  160Gd(p,n)160Tb excitation function was measured between 4-18 MeV using stacked-target activation at Lawrence Berkeley National Laboratory's 88-Inch Cyclotron. Nine copper and eight titanium foils served as proton fluence monitor foils, using the  natCu(p,x)65Zn,  natTi(p,x)48V, and  natTi(p,x)46Sc monitor standards, respectively. Variance minimization using an MCNP v.6.2 model reduced the systematic uncertainties in proton energy and fluence. A priori predictions of the  160Gd(p,n) reaction using ALICE, CoH, EMPIRE, and TALYS, as well as the TENDL database, are compared to the experimentally measured values.

Introduktion: Uppskattningsvis 40% av alla magnetresonanstomografiska (MRT) undersökningar som görs i Europa och USA utförs med gadoliniumbaserade kontrastmedel. Under det senaste decenniet har det i flera studier uppmärksammats att ansamling av gadolinium sker i olika strukturer i hjärnan. Patienter med multipel skleros följs regelbundet upp med MRT undersökningar och MRT med kontrastförstärkning är den vanligaste metoden för att urskilja nytillkomna patologiska förändringar. Utveckling inom teknologi och metoder inom artificiell intelligens har visat att det finns anledning att kartlägga om röntgensjuksköterskans arbete med undersökningar och läkemedel som administreras till patienter kan förändras så att det förebygger ansamling av gadolinium. Syfte: Syftet med denna litteraturöversikt var att kartlägga ansamlingen av gadoliniumkontrastmedel hos patienter med multipel skleros och hur artificiell intelligens kan tillämpas vid MRT för att minska användning av gadoliniumkontrast. Metod: Allmän litteraturöversikt där vetenskapliga artiklar av kvantitativ studiedesign har sökts fram genom databaserna CINAHL och PubMed. Resultat: Både makrocykliska och linjära gadoliniumbaserade kontrastmedel ansamlas i de basala ganglierna. Genom tillämpning av AI och CAD går det att framställa bilder med fullgod bildkvalitet och samtidigt reducera mängden kontrastmedel som administreras till patienten. Slutsats: Det behövs mer forskning om gadoliniumansamling för att nya rutiner och metoder ska kunna implementeras. Ansamling av gadolinium visar att det finns skäl att fortsätta utveckla nya metoder för uppföljning av sjukdomsförloppet hos MS-patienter. När det gäller AI inom medicinsk bilddiagnostik och magnetresonanstomografi finns många utvecklingsmöjligheter som kan bidra till minskning av gadoliniumbaserad kontrast i framtiden. Fortsatt forskning inom deep learning och CAD kan i framtiden utvecklas så att röntgensjuksköterskan får en mer självbestämmande funktion i bildframställni, Introduction: Approximately 40% of all magnetic resonance imaging (MRI) scans performed in Europe and the United States are performed with gadolinium based contrast agents. Over the past decade, several studies have shown a gadolinium deposition in various structures in the brain. Patients with multiple sclerosis are regularly followed up with MRI with contrast enhancement is the most common method for distinguishing new pathological changes. Developments in technology and methods in artificial intelligence have shown that there is reason to map out whether the radiographers work with examinations and drugs administered to patients can be changed so that the accumulation of gadolinium is prevented. Aim: The purpose of this literature review was to examine the accumulation of gadolinium contrast agents in patients with multiple sclerosis of gadolinium contrast agents in patients with multiple sclerosis and how artificial intelligence can be applied in MRI to reduce the use of gadolinium based contrast agents. Methods: General literature review where scientific articles of a quantitative nature have been searched through the databases CINAHL and PubMed. Results: Both macrocyclic and linear gadolinium based contrast agents are retained in the basal ganglia. With artificial intelligence and CAD, it is possible to obtain data with good quality and at the same time reduce the amount of gadolinium based contrasts to patients. Conclusions: More research on gadolinium accumulation is needed for new routines and methods to be implemented. Accumulation of gadolinium shows that there is reason to continue to develop new methods for monitoring the course of the disease in MS patients. Concerning AI in medical imaging and magnetic resonance imaging, there are many development opportunities that can contribute to the reduction of gadolinium contrast in the future. Continued research in deep learning and CAD can be developed in the future so that the X-ray nurse has a more self-det

Cardiac resynchronization therapy (CRT) is effective in selective heart failure (HF) patients, but non-response rate remains high. Positron emission tomography (PET) may provide a better insight into the pathophysiology of left ventricular (LV) remodeling; however, its role for evaluating and selecting patients for CRT remains uncertain. We investigated if regional LV glucose metabolism in combination with myocardial scar could predict response to CRT. Consecutive CRT-eligible HF patients underwent echocardiography, cardiac magnetic resonance (CMR), and F-fluorodeoxyglucose (FDG) PET within 1 week before CRT implantation. Echocardiography was additionally performed 12 months after CRT and end-systolic volume reduction ≥ 15% was defined as CRT response. Septal-to-lateral wall (SLR) FDG uptake ratio was calculated from static FDG images. Late gadolinium enhancement (LGE) CMR was analyzed semi-quantitatively to define scar extent. We evaluated 88 patients (67 ± 10 years, 72% males). F-FDG SLR showed a linear correlation with volumetric reverse remodeling 12 months after CRT (r = 0.41, p = 0.0001). In non-ischemic HF patients, low FDG SLR alone predicted CRT response with sensitivity and specificity of more than 80%; however, in ischemic HF patients, specificity decreased to 46%, suggesting that in this cohort low SLR can also be caused by the presence of a septal scar. In the multivariate logistic regression model, including low FDG SLR, presence and extent of the scar in each myocardial wall, and current CRT guideline parameters, only low FDG SLR and septal scar remained associated with CRT response. Their combination could predict CRT response with sensitivity, specificity, negative, and positive predictive value of 80%, 83%, 70%, and 90%, respectively. FDG SLR can be used as a predictor of CRT response and combined with septal scar extent, CRT responders can be distinguished from non-responders with high diagnostic accuracy. Further studies are needed to verify whet

Background: Atrial dilation is an important risk factor for atrial fibrillation (AF) and animal studies have found that acute atrial dilation shortens the atrial effective refractory period (AERP) and increases the risk of AF. Stretch activated ion channels (SACs) and calcium channels play a role in this. The expression profile and calcium dependent activation makes the small conductance calcium activated K+ channel (K(Ca)2.x) a candidate for coupling stretch induced increases in intracellular calcium through K+-efflux and thereby shortening of atrial refractoriness.Objectives: We hypothesized that K(Ca)2.x channel inhibitors can prevent the stretch induced shortening of AERP and protect the heart from AF.Methods: The effect of K(Ca)2 channel inhibitor (N-(pyridin-2-yl)-4-(pyridin-2-yl)thiazol-2-amine (ICA) 1 mu M) was investigated using the isolated perfused rabbit heart preparation. To stretch the left atrium (LA) a balloon was inserted and inflated. AERP and action potential duration (APD) were recorded before and after atrial stretch. AF was induced by burst pacing the LA at different degrees of atrial stretch.Results: Stretching of the LA by increasing the balloon pressure from 0 to 20 mmHg shortened the AERP by 8.6 +/- 1 ms. In comparison, the K(Ca)2 inhibitor ICA significantly attenuated the stretch induced shortening of AERP to 2.5 +/- 1.1 ms. Total AF duration increased linearly with atrial balloon pressure. This relationship was not found in the presence of ICA. ICA lowered the incidence of AF induction and total AF duration.Conclusion: The K(Ca)2 channel inhibitor ICA attenuates the acute stretch induced shortening of AERP and decreases stretch induced vulnerability to AF.

Introduktion: Uppskattningsvis 40% av alla magnetresonanstomografiska (MRT) undersökningar som görs i Europa och USA utförs med gadoliniumbaserade kontrastmedel. Under det senaste decenniet har det i flera studier uppmärksammats att ansamling av gadolinium sker i olika strukturer i hjärnan. Patienter med multipel skleros följs regelbundet upp med MRT undersökningar och MRT med kontrastförstärkning är den vanligaste metoden för att urskilja nytillkomna patologiska förändringar. Utveckling inom teknologi och metoder inom artificiell intelligens har visat att det finns anledning att kartlägga om röntgensjuksköterskans arbete med undersökningar och läkemedel som administreras till patienter kan förändras så att det förebygger ansamling av gadolinium. Syfte: Syftet med denna litteraturöversikt var att kartlägga ansamlingen av gadoliniumkontrastmedel hos patienter med multipel skleros och hur artificiell intelligens kan tillämpas vid MRT för att minska användning av gadoliniumkontrast. Metod: Allmän litteraturöversikt där vetenskapliga artiklar av kvantitativ studiedesign har sökts fram genom databaserna CINAHL och PubMed. Resultat: Både makrocykliska och linjära gadoliniumbaserade kontrastmedel ansamlas i de basala ganglierna. Genom tillämpning av AI och CAD går det att framställa bilder med fullgod bildkvalitet och samtidigt reducera mängden kontrastmedel som administreras till patienten. Slutsats: Det behövs mer forskning om gadoliniumansamling för att nya rutiner och metoder ska kunna implementeras. Ansamling av gadolinium visar att det finns skäl att fortsätta utveckla nya metoder för uppföljning av sjukdomsförloppet hos MS-patienter. När det gäller AI inom medicinsk bilddiagnostik och magnetresonanstomografi finns många utvecklingsmöjligheter som kan bidra till minskning av gadoliniumbaserad kontrast i framtiden. Fortsatt forskning inom deep learning och CAD kan i framtiden utvecklas så att röntgensjuksköterskan får en mer självbestämmande funktion i bildframställni, Introduction: Approximately 40% of all magnetic resonance imaging (MRI) scans performed in Europe and the United States are performed with gadolinium based contrast agents. Over the past decade, several studies have shown a gadolinium deposition in various structures in the brain. Patients with multiple sclerosis are regularly followed up with MRI with contrast enhancement is the most common method for distinguishing new pathological changes. Developments in technology and methods in artificial intelligence have shown that there is reason to map out whether the radiographers work with examinations and drugs administered to patients can be changed so that the accumulation of gadolinium is prevented. Aim: The purpose of this literature review was to examine the accumulation of gadolinium contrast agents in patients with multiple sclerosis of gadolinium contrast agents in patients with multiple sclerosis and how artificial intelligence can be applied in MRI to reduce the use of gadolinium based contrast agents. Methods: General literature review where scientific articles of a quantitative nature have been searched through the databases CINAHL and PubMed. Results: Both macrocyclic and linear gadolinium based contrast agents are retained in the basal ganglia. With artificial intelligence and CAD, it is possible to obtain data with good quality and at the same time reduce the amount of gadolinium based contrasts to patients. Conclusions: More research on gadolinium accumulation is needed for new routines and methods to be implemented. Accumulation of gadolinium shows that there is reason to continue to develop new methods for monitoring the course of the disease in MS patients. Concerning AI in medical imaging and magnetic resonance imaging, there are many development opportunities that can contribute to the reduction of gadolinium contrast in the future. Continued research in deep learning and CAD can be developed in the future so that the X-ray nurse has a more self-det

The design and development of contrast agents for magnetic resonance imaging (MRI) with improved chemical stability and higher contrasting capability for clinical translation compared to conventional contrast agents are still of great interest. In this study, a facile and universal approach was explored for controllable functionalization of red-emissive carbon nanodots (RCNDs) with diethylenetriaminepentaacetic anhydride (DTPA) for chelation of gadolinium. A series of accurate characterizations were used to control each step of the synthesis. The functionalization did not alter the band gap of the carbon nanodots, preserving their inherent far-red fluorescence. The as-prepared RCND-DTPA-Gd displayed a high colloidal stability with negligible Gd leakage. The nanodots also showed a better magnetic resonance relaxivity than commercial MRI agents. RCND-DTPA-Gd had good biocompatibility in vivo even at high doses. The systemically injected RCND-DTPA-Gd were found to be efficiently excreted through the renal route, a feature that further minimizes the potential toxicity risks. All these properties suggest that carbon nanodots can be well designed as efficient carriers of Gd, resulting in potential clinical tools as dual MRI/fluorescence functional probes for imaging applications. The approach described here could pave the pathway to a flexible strategy for the controllable functionalization of small-sized nanoparticles including carbon dots, rendering them more versatile. This work is expected to promote the future translation of carbon nanodots into clinical trials.

AHA guidelines recommend use of perfusion imaging for patient selection in the 6-24 h window. Recently, the safety of gadolinium-based contrast agents for MR perfusion imaging has been questioned based on findings that gadolinium accumulates in brain tissue. Regulatory bodies have recommended to limit the use of gadolinium-based contrast agents where possible. Focusing specifically on the time to maximum of the tissue residue function (Tmax) parameter, used in DAWN and DEFUSE 3, we hypothesized that half-dose scans would yield a similar Tmax delay pattern to full-dose scans. We prospectively recruited 10 acute ischemic stroke patients imaged with two perfusion scans at their follow-up visit, one with a standard dose gadolinium followed by a half-dose injection a median of 7 min apart. The brain was parcellated into a grid of 3 x 3 regions and the mean of the difference in Tmax between the 3 x 3 regions on the half- and full-dose Tmax maps was 0.1 s (iqr 0.38 s). The fraction of brain tissue that differed by no more than +/-1 s was 93.7%. In patients with normal or modest Tmax delays, half-dose gadolinium appears to provide comparable Tmax measurements to those of full-dose scans.Copyright © The Author(s) 2020.

AHA guidelines recommend use of perfusion imaging for patient selection in the 6-24 h window. Recently, the safety of gadolinium-based contrast agents for MR perfusion imaging has been questioned based on findings that gadolinium accumulates in brain tissue. Regulatory bodies have recommended to limit the use of gadolinium-based contrast agents where possible. Focusing specifically on the time to maximum of the tissue residue function (Tmax) parameter, used in DAWN and DEFUSE 3, we hypothesized that half-dose scans would yield a similar Tmax delay pattern to full-dose scans. We prospectively recruited 10 acute ischemic stroke patients imaged with two perfusion scans at their follow-up visit, one with a standard dose gadolinium followed by a half-dose injection a median of 7 min apart. The brain was parcellated into a grid of 3 x 3 regions and the mean of the difference in Tmax between the 3 x 3 regions on the half- and full-dose Tmax maps was 0.1 s (iqr 0.38 s). The fraction of brain tissue that differed by no more than +/-1 s was 93.7%. In patients with normal or modest Tmax delays, half-dose gadolinium appears to provide comparable Tmax measurements to those of full-dose scans.Copyright © The Author(s) 2020.

Zircon tailings containing rare earth metals are one of the alternative raw materials from secondary sources in Indonesia. The objective is to determine the effects of several operating conditions in the leaching process. Under specified leaching conditions including 2 M hydrochloric acid concentration, 10 g/100 ml solid-liquid ratio, and a temperature of 80 degrees C, the optimum rare earth metal leaching recovery was obtained. Under these conditions, as much as 60%, 74%, and 65% for cerium, lanthanum, and neodymium can be leached, respectively. Under the same conditions, HREE were leached as much as 71%, 61%, and 60% for erbium, gadolinium, and samarium, respectively. The leaching process was described using the kinetic model known as the Zhuravlev–Leshokin–Templeman model. Activation energy values for light and heavy rare earth element leaching were found to be 25.31 kJ/mol and 7.05 kJ/mol, respectively., Zircon tailings containing rare earth metals are one of the alternative raw materials from secondary sources in Indonesia. The objective is to determine the effects of several operating conditions in the leaching process. Under specified leaching conditions including 2 M hydrochloric acid concentration, 10 g/100 ml solid-liquid ratio, and a temperature of 80 degrees C, the optimum rare earth metal leaching recovery was obtained. Under these conditions, as much as 60%, 74%, and 65% for cerium, lanthanum, and neodymium can be leached, respectively. Under the same conditions, HREE were leached as much as 71%, 61%, and 60% for erbium, gadolinium, and samarium, respectively. The leaching process was described using the kinetic model known as the Zhuravlev–Leshokin–Templeman model. Activation energy values for light and heavy rare earth element leaching were found to be 25.31 kJ/mol and 7.05 kJ/mol, respectively.

Background: Atrial dilation is an important risk factor for atrial fibrillation (AF) and animal studies have found that acute atrial dilation shortens the atrial effective refractory period (AERP) and increases the risk of AF. Stretch activated ion channels (SACs) and calcium channels play a role in this. The expression profile and calcium dependent activation makes the small conductance calcium activated K+ channel (K(Ca)2.x) a candidate for coupling stretch induced increases in intracellular calcium through K+-efflux and thereby shortening of atrial refractoriness.Objectives: We hypothesized that K(Ca)2.x channel inhibitors can prevent the stretch induced shortening of AERP and protect the heart from AF.Methods: The effect of K(Ca)2 channel inhibitor (N-(pyridin-2-yl)-4-(pyridin-2-yl)thiazol-2-amine (ICA) 1 mu M) was investigated using the isolated perfused rabbit heart preparation. To stretch the left atrium (LA) a balloon was inserted and inflated. AERP and action potential duration (APD) were recorded before and after atrial stretch. AF was induced by burst pacing the LA at different degrees of atrial stretch.Results: Stretching of the LA by increasing the balloon pressure from 0 to 20 mmHg shortened the AERP by 8.6 +/- 1 ms. In comparison, the K(Ca)2 inhibitor ICA significantly attenuated the stretch induced shortening of AERP to 2.5 +/- 1.1 ms. Total AF duration increased linearly with atrial balloon pressure. This relationship was not found in the presence of ICA. ICA lowered the incidence of AF induction and total AF duration.Conclusion: The K(Ca)2 channel inhibitor ICA attenuates the acute stretch induced shortening of AERP and decreases stretch induced vulnerability to AF.

Literární část diplomové práce se zabývá výživou rostlin a přítomností kontaminantů v životním prostředí. Zaměřuje se na přítomnost prvků vzácných zemin, především gadolinia ve vodě a půdě s možným přestupem do zemědělských plodin a potravin. V experimentální části diplomové práce jsou popsány a navrženy analytické postupy pro sběr a přípravu vzorků hub a pro prvkovou analýzu kovů vzácných zemin s využitím metody ICP-MS. Získané výsledky analýzy jsou statisticky zpracovány a kriticky hodnoceny. Pro zpracované vzorky hub i data z literatury je vypočítána gadoliniová anomálie. Výstupní data jsou mezi sebou porovnána., The literary part of the diploma thesis deals with plant nutrition and the presence of contaminants in the environment. It focuses on the presence of rare earth elements, especially gadolinium in water and soil with a possible transfer to agricultural crops and food. The experimental part of the diploma thesis describes and proposes analytical procedures for the collection and preparation of fungal samples and for the elemental analysis of rare earth metals using the ICP-MS method. The obtained results of the analysis are statistically processed and critically evaluated. A gadolinium anomaly is calculated for processed fungal samples as well as for data from the literature. The output results are compared with each other., Fakulta chemicko-technologická, Studentka seznámila členy zkušební komise s obsahem své diplomové práce, poté byla seznámena s posudky vedoucího a oponenta diplomové práce. Studentka odpověděla na otázky oponenta diplomové práce a členů zkušební komise., Dokončená práce s úspěšnou obhajobou

Gadolinium-148 is one of the radionuclides of most concern that will be produced in the tungsten target of the European Spallation Source (ESS), as a by-product of the spallation reaction used by the facility to produce neutrons. Since 148Gd a pure alpha emitter, it is both very radiotoxic and difficult to measure. With its half-life of 75 years, it will remain in the environment for a long time if released from the facility during normal operation or after an accident. There are still uncertainties regarding the amounts that actually will be produced by spallation in the tungsten targets of the facility. As Gd-148 does not occur naturally in the environment, there is no information available about its analysis in environmental samples but a few studies provide data from irradiated target material analysed by alpha spectroscopy or inductively coupled plasma mass spectrometry (ICP-MS). This report is a continuation of the SSM project as described in the SSM report 2020:08, entitled “Identifying radiologically important ESS-specific radionuclides and relevant detection methods” that focused on the ESS-related radionuclides that will be the most relevant to study and monitor in the environment as well as the analytical techniques to detect them. The present report focuses on the rare earth elements (REEs), including their radioactive isotopes, in particular Gd-148, and is intended to highlight the knowledge gaps that exist regarding their fate in the specific environment of the ESS area. In the first part of the report, the available literature on radioecological models was reviewed, with emphasis on ESS-related radionuclides. The existing modelling programmes were surveyed as well as the most relevant environmental parameters and experimental radioecological data required to build models specific to the ESS.In the second part of the report, the area in the vicinity of the ESS was surveyed to identify the important producers of foodstuff, what plant species are grown i