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Relevant bibliographies by topics / DOTA-Gd

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Academic literature on the topic 'DOTA-Gd'

Author: Grafiati

Published: 4 June 2021

Last updated: 5 February 2022

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Journal articles on the topic "DOTA-Gd"

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LE MIGNON, MARIE-MADELEINE, CATHERINE CHAMBON, STEVE WARRINGTON, ROGER DAVIES, and BRUNO BONNEMAIN. "Gd-DOTA." Investigative Radiology 25, no. 8 (August 1990): 933–37. http://dx.doi.org/10.1097/00004424-199008000-00010.

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Zhan, Youyang, Rong Xue, Mengchao Zhang, Chuanling Wan, Xiaojing Li, Fengkui Pei, Changjiang Sun, and Lin Liu. "Synthesis and Evaluation of a Biocompatible Macromolecular Gadolinium Compound as a Liver-Specific Contrast Agent for MRI." Australian Journal of Chemistry 70, no. 3 (2017): 307. http://dx.doi.org/10.1071/ch16347.

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A new macromolecular biocompatible gadolinium chelate complex (PAI-N2-DOTA-Gd) as a liver-specific magnetic resonance imaging (MRI) contrast agent was synthesised and evaluated. An aspartic acid–isoleucine copolymer was chemically linked with Gd-DOTA via ethylenediamine to give PAI-N2-DOTA-Gd. In vitro, the T1-relaxivity of PAI-N2-DOTA-Gd (14.38 mmol–1⋅L⋅s–1, 0.5 T) was much higher than that of the clinically used Gd-DOTA (4.96 mmol–1⋅L⋅s–1, 0.5 T), with obvious imaging signal enhancement. In the imaging experiments in vivo, PAI-N2-DOTA-Gd exhibited good liver selectivity, and had a greater intensity enhancement (68.8 ± 5.6 %) and a longer imaging window time (30–70 min), compared to Gd-DOTA (21.1 ± 5.3 %, 10–30 min). Furthermore, the in vivo histological studies of PAI-N2-DOTA-Gd showed a low acute toxicity and desirable biocompatibility. The results of this study indicate that PAI-N2-DOTA-Gd is a feasible liver-specific contrast agent for MRI.

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Demine, Stéphane, Alexander Balhuizen, Vinciane Debaille, Lieke Joosten, Maïté Fereau, Satya Chilla, Isabelle Millard, et al. "Imaging of Human Insulin Secreting Cells with Gd-DOTA-P88, a Paramagnetic Contrast Agent Targeting the Beta Cell Biomarker FXYD2γa." Molecules 23, no. 9 (August 21, 2018): 2100. http://dx.doi.org/10.3390/molecules23092100.

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Non-invasive imaging and quantification of human beta cell mass remains a major challenge. We performed pre-clinical in vivo validation of a peptide previously discovered by our group, namely, P88 that targets a beta cell specific biomarker, FXYD2γa. We conjugated P88 with DOTA and then complexed it with GdCl3 to obtain the MRI (magnetic resonance imaging) contrast agent (CA) Gd-DOTA-P88. A scrambled peptide was used as a negative control CA, namely Gd-DOTA-Scramble. The CAs were injected in immunodeficient mice implanted with EndoC-βH1 cells, a human beta cell line that expresses FXYD2γa similarly to primary human beta cells. The xenograft-bearing mice were analyzed by MRI. At the end, the mice were euthanized and the CA biodistribution was evaluated on the excised tissues by measuring the Gd concentration with inductively coupled plasma mass spectrometry (ICP-MS). The MRI and biodistribution studies indicated that Gd-DOTA-P88 accumulates in EndoC-βH1 xenografts above the level observed in the background tissue, and that its uptake is significantly higher than that observed for Gd-DOTA-Scramble. In addition, the Gd-DOTA-P88 showed good xenograft-to-muscle and xenograft-to-liver uptake ratios, two potential sites of human islets transplantation. The CA shows good potential for future use to non-invasively image implanted human beta cells.

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Hodler, J., J. Orellano, S. Thurnher, B. Marincek, and G. von Schulthess. "Gd-DOTA bei muskuloskelettalen Erkrankungen." RöFo - Fortschritte auf dem Gebiet der Röntgenstrahlen und der bildgebenden Verfahren 153, no. 11 (November 1990): 535–39. http://dx.doi.org/10.1055/s-2008-1033433.

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Gazzi, Thais P., Luiz A. Basso, Diógenes S. Santos, and Pablo Machado. "A greener approach toward gadolinium-based contrast agents." RSC Adv. 4, no. 19 (2014): 9880–84. http://dx.doi.org/10.1039/c4ra00272e.

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Granata, Vincenza, Marco Cascella, Roberta Fusco, Nicoletta dell’Aprovitola, Orlando Catalano, Salvatore Filice, Vincenzo Schiavone, Francesco Izzo, Arturo Cuomo, and Antonella Petrillo. "Immediate Adverse Reactions to Gadolinium-Based MR Contrast Media: A Retrospective Analysis on 10,608 Examinations." BioMed Research International 2016 (2016): 1–6. http://dx.doi.org/10.1155/2016/3918292.

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Background and Purpose. Contrast media (CM) for magnetic resonance imaging (MRI) may determine the development of acute adverse reactions. Objective was to retrospectively assess the frequency and severity of adverse reactions associated with gadolinium-based contrast agents (GBCAs) injection in patients who underwent MRI.Material and Methods. At our center 10608 MRI examinations with CM were performed using five different GBCAs: Gd-BOPTA (MultiHance), Gd-DTPA (Magnevist), Gd-EOBDTPA (Primovist), Gd-DOTA (Dotarem), and Gd-BTDO3A (Gadovist).Results. 32 acute adverse reactions occurred, accounting for 0.3% of all administration. Twelve reactions were associated with Gd-DOTA injection (0.11%), 9 with Gd-BOPTA injection (0.08%), 6 with Gd-BTDO3A (0.056%), 3 with Gd-EOB-DTPA (0.028%), and 2 with Gd-DTPA (0.018%). Twenty-four reactions (75.0%) were mild, four (12.5%) moderate, and four (12.5%) severe. The most severe reactions were seen associated with use of Gd-BOPTA, with 3 severe reactions in 32 total reactions.Conclusion. Acute adverse reactions are generally rare with the overall adverse reaction rate of 0.3%. The most common adverse reactions were not severe, consisting in skin rash and hives.

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Ke, Xian-Sheng, Juan Tang, Zi-Shu Yang, and Jun-Long Zhang. "β-conjugation of gadolinium(III) DOTA complexes to zinc(II) porpholactol as potential multimodal imaging contrast agents." Journal of Porphyrins and Phthalocyanines 18, no. 10n11 (October 2014): 950–59. http://dx.doi.org/10.1142/s1088424614500758.

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Synthesis of two bimodal imaging agents consist of a hydrophobic zinc(II) tetrapentafluorophenylporpholactol core and a β-substituted hydrophilic Gd ( III ) DO3A (ZnLGd539) or DOTA (ZnLGd595) like moiety has been described (DO3A = 1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid, DOTA = 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid). Through β-conjugation approach, the absorption at deep red region increases compared to traditional conjugation methods at meso-position. More importantly, these new complexes possess largely improved ionic relaxitivites relative to the sole Gd ( III ) magnetic resonance imaging (MRI) agents such as Gd ( III ) DO3A and Gd ( III ) DOTA like complexes. Combining the optical and magnetic resonance measurements in aqueous media, the largely enhanced r1 relaxivities was attributed to the aggregation of ZnLGd539 and ZnLGd595 in aqueous media. Furthermore, fluorescence and magnetic resonance imaging experiment showed that both ZnLGd539 and ZnLGd595 can be applied as potential bimodal imaging contrast agents. Finally, both compounds showed no dark cytotoxicity and good photocytotoxicity (IC50 = 1.73 ± 0.13 and 1.52 ± 0.10 μM for ZnLGd539 and ZnLGd595 respectively) on Hela cells.

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Beaumont, Marine, Benjamin Lemasson, Régine Farion, Christoph Segebarth, Chantal Rémy, and Emmanuel L. Barbier. "Characterization of Tumor Angiogenesis in Rat Brain Using Iron-Based Vessel Size Index MRI in Combination with Gadolinium-Based Dynamic Contrast-Enhanced MRI." Journal of Cerebral Blood Flow & Metabolism 29, no. 10 (July 8, 2009): 1714–26. http://dx.doi.org/10.1038/jcbfm.2009.86.

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This study aimed at combining an iron-based, steady-state, vessel size index magnetic resonance imaging (VSI MRI) approach, and a gadolinium (Gd)-based, dynamic contrast-enhanced MRI approach (DCE MRI) to characterize tumoral microvasculature. Rats bearing an orthotopic glioma (C6, n=14 and RG2, n=6) underwent DCE MRI and combined VSI and DCE MRI 4 h later, at 2.35 T. Gd-DOTA (200 μmol of Gd per kg) and ultrasmall superparamagnetic iron oxide (USPIO) (200 μmol of iron per kg) were used for DCE and VSI MRI, respectively. C6 and RG2 gliomas were equally permeable to Gd-DOTA but presented different blood volume fractions and VSI, in good agreement with histologic data. The presence of USPIO yielded reduced Ktrans values. The Ktrans values obtained with Gd-DOTA in the absence and in the presence of USPIO were well correlated for the C6 glioma but not for the RG2 glioma. It was also observed that, within the time frame of DCE MRI, USPIO remained intravascular in the C6 glioma whereas it extravasated in the RG2 glioma. In conclusion, VSI and DCE MRI can be combined provided that USPIO does not extravasate with the time frame of the DCE MRI experiment. The mechanisms at the origin of USPIO extravasation remain to be elucidated.

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Randolph, Lyndsay M., Clare L. M. LeGuyader, Michael E. Hahn, Christopher M. Andolina, Joseph P. Patterson, Robert F. Mattrey, Jill E. Millstone, Mauro Botta, Miriam Scadeng, and Nathan C. Gianneschi. "Polymeric Gd-DOTA amphiphiles form spherical and fibril-shaped nanoparticle MRI contrast agents." Chemical Science 7, no. 7 (2016): 4230–36. http://dx.doi.org/10.1039/c6sc00342g.

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A Gd³⁺-coordinated polymerizable analogue of the MRI contrast agent Gd-DOTA was used to prepare amphiphilic block copolymers, with hydrophilic blocks composed entirely of the polymerized contrast agent.

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Bourrinet, Philippe, Eric Martel, Abdel I. El Amrani, Pascal Champeroux, Serge Richard, Nicolas Fauchou, Franck Le Coz, Milo Drici, Bruno Bonnemain, and Sophie Gaillard. "Cardiovascular Safety of Gadoterate Meglumine (Gd-DOTA)." Investigative Radiology 42, no. 2 (February 2007): 63–77. http://dx.doi.org/10.1097/01.rli.0000251565.61487.1a.

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Dissertations / Theses on the topic "DOTA-Gd"

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Kaufels, Nicola. "MRT-Myokarduntersuchungen zur Vitalität und Perfusion mit P792 im Vergleich zu Gd-DOTA an Schweinen nach Induktion eines akuten Herzinfarktes /." Berlin : Mensch-und-Buch-Verl, 2005. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=014780625&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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Kaufels, Nicola [Verfasser]. "MRT-Myokarduntersuchungen zur Vitalität und Perfusion mit P792 im Vergleich zu Gd-DOTA an Schweinen nach Induktion eines akuten Herzinfarktes / vorgelegt von Nicola Kaufels." Berlin : Mensch-und-Buch-Verl, 2006. http://d-nb.info/979208319/34.

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Perrat, Emilie. "Impacts environnementaux des agents de contraste à base de Gadolinium : situation locale, approche cellulaire et in vivo." Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0370/document.

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L’utilisation de plus en plus fréquente des agents de contraste à base de Gd (AC-Gd) au cours des examens d’Imagerie par Résonnance Magnétique (IRM), engendre le rejet de ces produits pharmaceutiques dans les eaux usées retraitées en STation d’EPuration (STEP). En l’absence de retraitement spécifique de ces AC-Gd en STEP, ils sont rejetés dans le milieu aquatique, où de nombreuses études ont relevé leur présence aussi bien dans les eaux de surface que dans les eaux souterraines et jusqu’à l’eau du robinet. Le manque de connaissances concernant les effets des AC-Gd suite à leur rejet a mis en évidence la nécessité d’étudier leurs impacts environnementaux sur les organismes vivants dans les milieux aquatiques. Dans ce contexte, nous avons choisi de déterminer les concentrations en Gd d’origine anthropique à proximité de rejets de STEP et de zones de captage en eau potable situés en région Lorraine. Nos mesures ont permis de montrer la présence Gd d’origine anthropique sur l’ensemble des échantillons prélevés, avec des concentrations mesurées comprises de quelques ng(Gd)/L à quelques dizaines de µg(Gd)/L. Ces concentrations de Gd anthropique seraient dues à la présence d’AC-Gd. Nous nous sommes plus particulièrement intéressés aux effets de l’AC-Gd le plus stable et l’un des plus fréquemment commercialisé : le Gd-DOTA (Dotarem®). Pour cela, nous avons choisis plusieurs espèces représentatives des taxons rencontrés dans les cours d’eau Lorrains. Des essais ont été menés en conditions contrôlées de laboratoire afin de mesurer l’accumulation du Gd-DOTA dans les tissus et les effets de l’AC-Gd ont été appréhendés au travers de mesures de croissance, de reproduction et de mortalité au niveau individuel chez les microalgues vertes unicellulaires (Chlorella vulgaris et Pseudokirchneriella subcapitata), chez un microcrustacé (Daphnia magna) et chez un vertébré aquatique (Danio rerio) exposés à des concentrations en Gd-DOTA réalistes d’un point de vue environnemental. L’accumulation du Gd-DOTA a aussi été mesurée chez les bivalves (Corbicula fluminea et Dresseina rostriformis bugensis) et comparée à des mesures d’accumulation du Gd in situ. Les réponses physiologiques des bivalves ont été évaluées à l’aide d’une batterie de 11 biomarqueurs dans leurs branchies et leur glande digestive. Les effets de l’AC-Gd ont également été étudiés in vitro sur des fibroblastes de D. rerio (cellules ZF4 - ATCC-2050). Nos travaux ont montré que les AC-Gd et le Gd-DOTA en particulier étaient responsables d’effets écotoxiques indirects à différents niveaux d’organisation biologiques. Seuls les bivalves accumulent le Gd-DOTA mais tous les individus semblent mettre en place des mécanismes de dépuration pour parer à la toxicité de l’AC-Gd. Les résultats obtenus au cours de cette recherche ont confirmé la nécessité d’un suivi des concentrations en AC-Gd dans le milieu aquatique et la nécessité d’approfondir les études de l’écotoxicité de ces produits pharmaceutiques. Ceci pourra aboutir à une évaluation pertinente de leur risque environnemental et de proposer des solutions pour la gestion environnementale de ces composés
The increasing use of Gadolinium-based Contrast Agents (Gd-CA) for Magnetic Resonance Imaging (MRI) results in their rejection in Waste Water Treatment Plants (WWTPs). Due to the lack of specific recycling process in European WWTPs, these pharmaceutical produces enter the aquatic environment from river to tap water. The effects of Gd-CA in aquatic media have been not studied yet. The lack of knowledge about these effects highlighted the need to study their environmental impacts on aquatic organisms. In this context, we decided to measure anthropogenic concentrations of Gd in the aquatic environment in the Lorraine region (France) closed to WWTPs outputs and catchment areas used for drinking water. Our measurements underlined the presence of anthropogenic Gd on all the collected samples at concentrations ranging from few ng/L to several dozen of µg/L. In this research we focused on the effects of the most frequently used Gd-CA, the gadoteric acid (Gd-DOTA - Dotarem®) which is also the most stable one. Several representative species of aquatic environment were selected for ecotoxicological assays: i.e. unicellular green microalgae (Chlorella vulgaris and Pseudokirchneriella subcapitata), microcrustacean (Daphnia magna) and aquatic vertebrate (Danio rerio). Assays were conducted in laboratory under controlled conditions as well as in situ. Gd-DOTA accumulation was measured in the tissues of the different organisms. Environmental realistic concentrations of Gd-CA were used to assess their effects at the individual level by means of growth, reproduction and mortality measurements. The Gd-DOTA accumulation was also measured in bivalves’ tissues (Corbicula fluminea and Dresseina rostriformis bugensis) and compared to Gd ones in situ in these organisms. Physiological responses were assessed based on a battery of 11 complementary biomarkers measured in the digestive gland and in the gills of both bivalve species. At cellular level, the effects of Gd-DOTA were studied in vitro on D. rerio fibroblasts (ZF4 – ATCC-2050). Indirect ecotoxicological effects of Gd-CA and of Gd-DOTA especially have been highlighted at all biological levels. Accumulation of Gd-DOTA was observed in bivalves only, but defense systems were mobilized in all organisms to limit toxicity. Our results demonstrated that following both research on ecotoxicological effects of the Gd-CA and evolution of their concentrations in aquatic ecosystem are necessary to assess more precisely their environmental risk and to propose solutions for their environmental management

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Schürholz, Hellmut Andreas [Verfasser], and Arno [Akademischer Betreuer] Bücker. "Vergleich der experimentellen Kontrastmittel P792 und P846 gegenüber Gd-DOTA hinsichtlich Kontrastmittelanreicherung und Kontrast-zu-Rausch-Verhältnis bei experimentell erzeugten Hirngliomen in Ratten mittels MRT bei 3T / Hellmut Andreas Schürholz. Betreuer: Arno Bücker." Saarbrücken : Saarländische Universitäts- und Landesbibliothek, 2011. http://d-nb.info/1051434513/34.

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Ait, Sarkouh Rafik. "Synthèse de conjugués avec la toxine de Shiga pour des thérapies anticancéreuses ciblées et la détection de tumeurs par IRM." Thesis, Paris 5, 2012. http://www.theses.fr/2012PA05P641.

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Une des principales limites de la chimiothérapie du cancer est le manque de sélectivité des agents cytotoxiques vis-à-vis des cellules tumorales, entrainant de nombreux effets secondaires. L’intérêt de la vectorisation est d’administrer l’agent cytotoxique sélectivement aux cellules cancéreuses et ainsi d’éviter de faire subir l’action du médicament aux cellules saines. Cette thèse a pour but de synthétiser des prodrogues multivalentes qui utilisent la sous unité B de la toxine de Shiga (STxB) comme agent de vectorisation, ciblant préférentiellement les cellules cancéreuses Gb3-positives. Les deux agents cytotoxiques choisis, un dérivé de la camptothécine et de l’auristatine, ont été liés de façon covalente auvecteur via un espaceur bifonctionnel clivable par le glutathion. L’espaceur a également été remplacé par un répartiteur multivalent susceptible de délivrer une quantité plus importante d’agent cytotoxique à l’intérieur des cellules tumorales.Parallèlement à ce projet de vectorisation d’un agent thérapeutique, des sondes IRM capables de marquer in vivo les tumeurs possédant à leur surface le récepteur Gb3 ont été synthétisées. L’IRM a une très bonne définition spatiale, mais souffre d’un manque de sensibilité. Pour augmenter le contraste, nous avons utilisé une stratégie reposant sur lamultivalence des espaceurs liés à des molécules de DOTA-Gd, un agent de contraste classiquement utilisé en IRM. Ces dernières ont été fixées à STxB via un répartiteur multivalent (des nano-bâtonnets d’or). Le signal IRM est plus intense et donc plus facile à détecter. Enfin, nous avons développé une nouvelle méthode chimique basée sur la ligationoxime pour optimiser la création de conjugués entre STxB et des antigènes comme outils de vaccination. Le conjugué STxB-ovalbumine a permis une meilleure présentation de l’antigène par les cellules dendritiques, conduisant chez la souris à une induction efficace de lymphocytes T
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Lei, Iok-Sun, and 李毓璇. "Synthesis of DOTA-OIA and Physicochemical Characterization of Its Gd(III) Complex." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/03589625003821062214.

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碩士
高雄醫學大學
醫藥暨應用化學研究所
98
This research is focusing on developing the Gd ligands which have potential to targeting contrast agent. The carboxylic acid terminal of 5-(1-bromoacatamido)-2,3-dihydro-1-oxo-1H-indene-2-acetic acid can be modified with appropriate peptide or other target specific residue to develop target specific MRI contrast agent for potential application in tumor imaging. This research is to develop a ligand which has the character of optimal lipophilicity. The calculated value obtained for [Gd(DOTA-OIA)] (miLogP = -4.147) is similar to that of MS-325 (-4.575) which is clinically used blood pool MRI contrast agent. Together with the help of 1H-NMR、and the identification of LC-MS. I have successfully synthesized 5-(1-bromoacatamido) -2,3- dihydro-1- oxo-1H-indene-2-acetic acid. With the result of identification of LC-MS, its molecule weight is 327.93 which meets the expectation value. The synthesis of [Gd(DOTA-OIA)] is still in progress and expected to complete soon. The synthesis of [Gd(DOTA-OIA)] will be completed and get the spectral of last step. By using 20MHz relaxometor to measure the relaxivity.

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Wang, Yan-Syun, and 王彥勛. "Synthesis and Characterization of [Gd(DOTA-iRGD)] as a Tumor Specific MRI Contrast Agent." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/09960076364742716921.

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碩士
國立交通大學
生物科技學系
99
The MRI contrast agents bearing peptides as target moiety can be used to differentiate tumor tissue with normal one, the contrast of MR imaging will evaluate by specific binding to tumor tissue. iRGD is a cyclic peptide sequence compose of nine amino acid , with ability of brining material to αv integrin over expression or angiogenic endothelial cells and be uptake by cell. iRGD bearing MR contrast agent [Gd(DOTA-iRGD)] is designed and synthesized, expect it will evaluate the contrast of MR imaging by cell internalize and discuss it chemical and physical property. Relaxivity (r1) of [Gd(DOTA- iRGD)] under 20 MHz, 37.0 ± 0.1 ℃ is 4.91 ± 0.03 mM-1s-1. In cytotoxicity assay, [Gd(DOTA-iRGD)] induce apoptosis of PC-3, an αv integrin over expression cell line, but has no significant effect to lower expression HT-1080 cell line even at high concentration. In vitro MR imaging show that PC-3 cell line can evaluate more contrast than αv integrin lower expression HT-1080 cell line.

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Fontes, André Filipe Gomes Soares. "DOTA-based Ga(III) and Gd(III) chelates for medical imaging (PET, SPECT and MRI)." Doctoral thesis, 2015. http://hdl.handle.net/1822/38710.

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PhD Thesis in Sciences Specialization in Chemistry
The work developed aimed at the design, synthesis and characterization of new Gd(III) and Ga(III) chelates with potential application as imaging probes. The initial part of the work is focused on the synthesis of new DOTA-based bifunctional ligands. The chelator DOTA-AHA (1,4,7,10-tetraazacyclododecane-1-[(6-amino)hexanoic]- 4,7,10-triacetic acid) was successfully synthesized and characterized. This ligand was the starting point for the development of three sets of molecular constructs, which include dimeric ligands, PEGylated chelators and c(RGDWK) peptide bioconjugates. The Gd(III) chelates of DOTA-AHA, dimeric ligands and DOTA-AHA PEGylated ligands were obtained. All Gd(III) chelates were studied by variable temperature 1H NMRD (nuclear magnetic relaxation dispersion) and 17O NMR (nuclear magnetic resonance) spectroscopy in order to measure the relaxivity and the parameters that govern it. Gd(DOTA-AHA) and the binuclear chelates form weakly bound aggregates and even if the aggregates contain only 10 to 15% of the total amount of Gd(III) ions a marked increase in relaxivity between 30 and 100 MHz is observed. PEGylation did not show to be a very efficient process for relaxivity improvement. Despite the moderate water exchange rates of the PEGylated Gd(III) chelates and the high global rotational correlation times, these chelates present lower relaxivity values than the binuclear chelates. The distance between the two Gd(III) centers in the binuclear compounds has been determined by double electron-electron resonance (DEER) experiments and by molecular modelling studies giving comparable distances. 1H NMR spectra of paramagnetic lanthanide chelates of DOTA-A(PEG750)HA were recorded at different temperatures. The data obtained gave information on the structure and dynamics of the chelates in solution. In vitro studies with 67Ga-radiolabeled DOTA-AHA and DOTA-A(PEG750)HA showed that both chelates are extremely hydrophilic. The lack of biospecificity of 67Ga(DOTA-AHA) and [67Ga(DOTA-A(PEG750)HA)]- is revealed by their biodistribution profiles, which show that both radiolabeled chelates have significant uptake in major tissues.
O trabalho desenvolvido teve como objectivo o desenho, síntese e caracterização de novos quelatos de Gd(III) e Ga(III) com potencial aplicação como agentes de imagem. A parte inicial do trabalho focou-se na síntese de novos ligandos funcionais do tipo DOTA. O ligando DOTA-AHA (ácido 1,4,7,10-tetraazaciclododecano-1-[(6- amino)hexanóico]-4,7,10-triacético) foi sintetizado e caracterizado com sucesso. Este ligando foi o ponto de partida para o desenvolvimento de ligandos diméricos, ligandos PEGuilados e bioconjugados com o péptido c(RGDWK). Preparam-se os quelatos de Gd(III) do ligando DOTA-AHA, dos ligandos diméricos e dos ligandos PEGuilados. Todos os quelatos de Gd(III) foram estudados por DRMN (dispersão de relaxação magnética nuclear) e RMN (ressonância magnética nuclear) de 17O, de modo a obter os valores de relaxividade e os parâmetros que a afectam. O quelato Gd(DOTA-AHA) e os quelatos binucleares formam agregados fracamente ligados e apesar de os agregados só conterem 10 a 15% da quantidade total de iões Gd(III) verifica-se um aumento acentuado na relaxividade para frequências entre 30 e 100 MHz. A PEGuilação mostrou ser um processo pouco eficiente para melhorar a relaxividade. Apesar das constantes de troca de água dos respectivos complexos de Gd(III) se mostrarem consideráveis e dos seus elevados tempos de correlação rotacional globais, estes quelatos apresentam valores de relaxividade inferiores à dos quelatos binucleares. A distância entre os dois centros de Gd(III) nos compostos binucleares foi determinada por ressonância dupla electrão-electrão (RDEE) e por estudos de modelação molecular, tendo sido obtidos resultados comparáveis. Estudos de 1H RMN dos quelatos de DOTA-A(PEG750)HA com lantanídeos paramagnéticos foram efectuados a diferentes temperaturas. Os dados recolhidos forneceram informação sobre a estrutura e dinâmica destes quelatos em solução. Estudos in vitro com os ligandos DOTA-AHA e DOTA-A(PEG750)HA marcados com 67Ga mostraram que ambos os quelatos são extremamente hidrofílicos. A falta de bioespecificidade de 67Ga(DOTA-AHA) e [67Ga(DOTA-A(PEG750)HA)]- é evidenciada através dos perfis de biodistribuição destes radiocomplexos.
Fundação para a Ciência e Tecnologia PhD grant SFRH /BD/63676/2009.

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Liu, Wan-Chun, and 劉婉淳. "The synthetic and characteristic study of 19F MRI contrast agent [Gd(DOTA-CF3)] to detect H2S." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/69612816342192588141.

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Abstract:

碩士
國立交通大學
生物資訊及系統生物研究所
103
H2S, an important small molecule in the body, performs an indispensable role in many biological activities. H2S detection using MRI in human body plays a crucial role in Molecular Imaging clinical trial with potential outcome. In this study, we designed a Gadolinium complex [Gd(DOTA-CF3)] containing a hydrophilic ligand with fluorine as the functional site to detect the H2S. Upon reaction with biothiols the PRE effect in complex enhances the paramagnetism between Gadolinium and fluorine and this helps to shorten 19F MRI signals which can be detected easily using 19F-NMR. Results showed that [Gd(DOTA-CF3)] selectively detects H2S among the biothiols .

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Reinländer, Claudia [Verfasser]. "MRT-Kontrastmittel für das Knochenmark : vergleichende experimentelle Untersuchungen von USPIO, SPIO und Gd-DOTA / vorgelegt von Claudia Reinländer." 2003. http://d-nb.info/969510896/34.

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Book chapters on the topic "DOTA-Gd"

1

Kravtzoff, Roger, Eric Urvoase, Catherine Chambon, and Claude Ropars. "Gd-DOTA Loaded into Red Blood Cells, a New Magnetic Resonance Imaging Contrast Agents for Vascular System." In The Use of Resealed Erythrocytes as Carriers and Bioreactors, 347–54. Boston, MA: Springer US, 1992. http://dx.doi.org/10.1007/978-1-4615-3030-5_42.

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2

Parizel, P. M., H. R. Degryse, J. Gheuens, J. J. Martin, M. Van Vyve, C. De la Porte, P. Selosse, P. Van de Heyning, and A. M. De Schepper. "Initial Clinical Results with the Paramagnetic MR Contrast Agent Gd-DOTA in the Diagnosis of Central Nervous System Lesions." In Imaging of Brain Metabolism Spine and Cord Interventional Neuroradiology Free Communications, 559–62. Berlin, Heidelberg: Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/978-3-642-74337-5_159.

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