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Kastl M, Grémy O, Lamart S, Giussani A, Li WB, Hoeschen C. Modelling DTPA therapy following Am contamination in rats. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2023; 62:483-495. [PMID: 37831188 PMCID: PMC10628027 DOI: 10.1007/s00411-023-01046-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 09/25/2023] [Indexed: 10/14/2023]
Abstract
A major challenge in modelling the decorporation of actinides (An), such as americium (Am), with DTPA (diethylenetriaminepentaacetic acid) is the fact that standard biokinetic models become inadequate for assessing radionuclide intake and estimating the resulting dose, as DTPA perturbs the regular biokinetics of the radionuclide. At present, most attempts existing in the literature are empirical and developed mainly for the interpretation of one or a limited number of specific incorporation cases. Recently, several approaches have been presented with the aim of developing a generic model, one of which reported the unperturbed biokinetics of plutonium (Pu), the chelation process and the behaviour of the chelated compound An-DTPA with a single model structure. The aim of the approach described in this present work is the development of a generic model that is able to describe the biokinetics of Am, DTPA and the chelate Am-DTPA simultaneously. Since accidental intakes in humans present many unknowns and large uncertainties, data from controlled studies in animals were used. In these studies, different amounts of DTPA were administered at different times after contamination with known quantities of Am. To account for the enhancement of faecal excretion and reduction in liver retention, DTPA is assumed to chelate Am not only in extracellular fluids, but also in hepatocytes. A good agreement was found between the predictions of the proposed model and the experimental results for urinary and faecal excretion and accumulation and retention in the liver. However, the decorporation from the skeletal compartment could not be reproduced satisfactorily under these simple assumptions.
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Affiliation(s)
- Manuel Kastl
- Institute of Radiation Medicine, Helmholtz Center Munich, German Research Center for Environmental Health, Neuherberg, Germany.
| | - Olivier Grémy
- Laboratoire de Radio Toxicologie, CEA, Université de Paris-Saclay, Arpajon, France
| | - Stephanie Lamart
- Laboratoire de Radio Toxicologie, CEA, Université de Paris-Saclay, Arpajon, France
- Laboratoire d'Evaluation de la Dose Interne, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSE-SANTE/SDOS/LEDI, Fontenay-aux-Roses, France
| | - Augusto Giussani
- Division of Medical and Occupational Radiation Protection, Federal Office for Radiation Protection, Oberschleißheim, Germany
| | - Wei Bo Li
- Institute of Radiation Medicine, Helmholtz Center Munich, German Research Center for Environmental Health, Neuherberg, Germany
- Division of Medical and Occupational Radiation Protection, Federal Office for Radiation Protection, Oberschleißheim, Germany
| | - Christoph Hoeschen
- Institut für Medizintechnik, Otto-Von-Guericke University Magdeburg, Magdeburg, Germany
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Grémy O, Mougin-Degraef M, Devilliers K, Berdal M, Laroche P, Miccoli L. DTPA-Coated Liposomes as a New Delivery Vehicle for Plutonium Decorporation. Radiat Res 2021; 195:77-92. [PMID: 33180911 DOI: 10.1667/rade-20-00142.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 10/05/2020] [Indexed: 11/03/2022]
Abstract
Administration of diethylenetriaminepentaacetic acid (DTPA) is the treatment approach used to promote the decorporation of internalized plutonium. Here we evaluated the efficacy of PEGylated liposomes coated with DTPA, primarily designed to prevent enhanced plutonium accumulation in bones, compared to marketed nonliposomal DTPA and liposomes encapsulating DTPA. The comparative effects were examined in terms of reduction of activity in tissues of plutonium-injected rats. The prompt treatment with DTPA-coated liposomes elicited an even greater efficacy than that with liposome-encapsulated DTPA in limiting skeletal plutonium. This advantage, undoubtedly due to the anchorage of DTPA to the outer layer of liposomes, is discussed, as well as the reason for the loss of this superiority at delayed times after contamination. Plutonium complexed with DTPA-coated liposomes in extracellular compartments was partly diverted into the liver and the spleen. These complexes and those directly formed inside hepatic and splenic cells appeared to be degraded, then released from cells at extremely slow rates. This transitory accumulation of activity, which could not be counteracted by combining both liposomal forms, entailed an underestimation of the efficacy of DTPA-coated liposomes on soft tissue plutonium until total elimination probably more than one month after treatment. DTPA-coated liposomes may provide the best delivery vehicle of DTPA for preventing plutonium deposition in tissues, especially in bone where nuclides become nearly impossible to remove once fixed. Additional development efforts are needed to limit the diversion or to accelerate cell release of plutonium bound to DTPA-coated liposomes, using a labile bond for DTPA attachment.
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Affiliation(s)
- Olivier Grémy
- Laboratoire de RadioToxicologie, CEA, Université de Paris-Saclay, Bruyères-le-Châtel, France
| | - Marie Mougin-Degraef
- CRCINA, INSERM, CNRS, Université d'Angers, Université de Nantes, Nantes, France.,Nuclear Medicine, University Hospital, Nantes, France
| | - Karine Devilliers
- Laboratoire de RadioToxicologie, CEA, Université de Paris-Saclay, Bruyères-le-Châtel, France
| | - Marion Berdal
- Nuclear Medicine, University Hospital, Nantes, France
| | - Pierre Laroche
- Direction of Health, Security, Environment and Radioprotection, ORANO, Paris, France
| | - Laurent Miccoli
- Laboratoire de RadioToxicologie, CEA, Université de Paris-Saclay, Bruyères-le-Châtel, France
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Cook MC, Brey RR. Identification of Volume of Distribution for 239Pu in Rats. HEALTH PHYSICS 2021; 120:367-377. [PMID: 33229944 DOI: 10.1097/hp.0000000000001337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
ABSTRACT The work within identifies the volume of distribution (VD) of plutonium using data from studies in which rats were administered an intravenous bolus injection of 239Pu4+-citrate. The research investigated two separate datasets. Data published by Durbin and colleagues in "Plutonium Deposition Kinetics in Rats" and studies conducted by Lovelace Respiratory Research Institute (LRRI) were examined. The goal of this research was to identify a value of VD consistent with the known biological behavior of plutonium. The identified VD is necessary to develop a physiologically-based pharmacokinetic (PBPK) model. The creation of a PBPK model describing the behavior of plutonium in the body enables the comparison of transfer rates to validate the biokinetic models currently in use for internal dosimetry purposes. The VD of a substance describes the distribution between intracellular and extracellular fluid compartments, providing information such as cellular uptake and protein binding. The VD time profiles and values found using the Durbin data were consistent with known behavior of plutonium. The VD values found using data provided by LRRI were not consistent with known behavior of plutonium; however, the VD time profiles generated may still be of use for PBPK modeling.
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Affiliation(s)
- Madeline C Cook
- Department of Health Physics, Idaho State University, 921 S 8th Ave, Pocatello, ID 83209
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Dumit S, Bertelli L, Klumpp JA, Poudel D, Waters TL. Chelation Modeling: The Use of Ad Hoc Models and Approaches to Overcome a Dose Assessment Challenge. HEALTH PHYSICS 2020; 118:193-205. [PMID: 31833972 DOI: 10.1097/hp.0000000000001134] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Chelating agents are administered to treat significant intakes of radioactive elements such as plutonium, americium, and curium. These drugs may be used as a medical countermeasure after radiological accidents and terrorist acts. The administration of a chelating agent, such as Ca-DTPA or Zn-DTPA, affects the actinide's normal biokinetics. It enhances the actinide's rate of excretion, posing a dose assessment challenge. Thus, the standard biokinetic models cannot be directly applied to the chelation-affected bioassay data in order to assess the radiation dose. The present study reviews the scientific literature, from the early 1970s until the present, on the different studies that focused on developing new chelation models and/or modeling of bioassay data affected by chelation treatment. Although scientific progress has been achieved, there is currently no consensus chelation model available, even after almost 50 y of research. This review acknowledges the efforts made by different research groups, highlighting the different methodology used in some of these studies. Finally, this study puts into perspective where we were, where we are, and where we are heading in regards to chelation modeling.
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Affiliation(s)
- Sara Dumit
- Los Alamos National Laboratory, Los Alamos, NM
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Gremy O, Miccoli L. Comments on "Improved Modeling of Plutonium-DTPA Decorporation" (Radiat Res 2019; 191:201-10). Radiat Res 2019; 192:680-681. [PMID: 31556845 DOI: 10.1667/rr00og.1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Olivier Gremy
- Laboratoire de RadioToxicologie, CEA, Université de Paris-Saclay, Bruyères le Châtel, France
| | - Laurent Miccoli
- Laboratoire de RadioToxicologie, CEA, Université de Paris-Saclay, Bruyères le Châtel, France
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Dumit S, Avtandilashvili M, Strom DJ, McComish SL, Tabatadze G, Tolmachev SY. Improved Modeling of Plutonium-DTPA Decorporation. Radiat Res 2018; 191:201-210. [DOI: 10.1667/rr15188.1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Sara Dumit
- U.S. Transuranium and Uranium Registries, Washington State University, Richland, Washington 99354–4959
| | - Maia Avtandilashvili
- U.S. Transuranium and Uranium Registries, Washington State University, Richland, Washington 99354–4959
| | - Daniel J. Strom
- U.S. Transuranium and Uranium Registries, Washington State University, Richland, Washington 99354–4959
| | - Stacey L. McComish
- U.S. Transuranium and Uranium Registries, Washington State University, Richland, Washington 99354–4959
| | - George Tabatadze
- U.S. Transuranium and Uranium Registries, Washington State University, Richland, Washington 99354–4959
| | - Sergei Y. Tolmachev
- U.S. Transuranium and Uranium Registries, Washington State University, Richland, Washington 99354–4959
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Grémy O, Miccoli L, Lelan F, Bohand S, Cherel M, Mougin-Degraef M. Delivery of DTPA through Liposomes as a Good Strategy for Enhancing Plutonium Decorporation Regardless of Treatment Regimen. Radiat Res 2018. [DOI: 10.1667/rr14968.1] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Olivier Grémy
- Laboratoire de RadioToxicologie, CEA, Université de Paris-Saclay, Bruyères le Châtel, France
| | - Laurent Miccoli
- Laboratoire de RadioToxicologie, CEA, Université de Paris-Saclay, Bruyères le Châtel, France
| | - Faustine Lelan
- Laboratoire de RadioToxicologie, CEA, Université de Paris-Saclay, Bruyères le Châtel, France
| | | | - Michel Cherel
- CRCINA, Inserm, CNRS, Université d'Angers, Université de Nantes, Nantes, France
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Grémy O, Coudert S, Renault D, Miccoli L. Decorporation Approach after Rat Lung Contamination with Plutonium: Evaluation of the Key Parameters Influencing the Efficacy of a Protracted Chelation Treatment. Radiat Res 2017; 188:552-561. [PMID: 28945525 DOI: 10.1667/rr14782.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
While the efficacy of a protracted zinc (Zn)- or calcium (Ca)-diethylenetriaminepentaacetic acid (DTPA) treatment in reducing transuranic body burden has already been demonstrated, questions about therapeutic variables remain. In response to this, we designed animal experiments primarily to assess both the effect of fractionation of a given dose and the effect of the frequency of dose fraction, with the same total dose. In our study, rats were contaminated intravenously with plutonium (Pu) then treated several days later with Ca-DTPA given at once or in various split-dose regimens cumulating to the same total dose and spread over several days. Similar efficacies were induced by the injection of the total dose or by splitting the dose in several smaller doses, independent of the number of doses and the dose level per injection. In a second study, rats were pulmonary contaminated, and three weeks later they received a Ca-DTPA dose 11-fold higher than the maximal daily recommended dose, administered either as a single bolus or as numerous multiple injections cumulating to the same dose, based on different injection frequency schedules. Independent of frequency schedule, the various split-dose regimens spread over weeks/months were as efficient as single delivery of the total dose in mobilizing lung plutonium, and had a therapeutic advantage for removal of retained hepatic and bone plutonium burdens. We concluded that cumulative dose level was a therapeutic variable of greater importance than the distribution of split doses for the success of a repeated treatment regimen on retained tissue plutonium. In addition, pulmonary administration of clodronate, which aims at killing alveolar macrophages and subsequently releasing their plutonium content, and which is associated with a continuous Ca-DTPA infusion regimen, suggested that the efficacy of injected Ca-DTPA in decorporating lung deposit is limited, due to its restricted penetration into alveolar macrophages and not because plutonium, as a physicochemical form, is unavailable for chelation.
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Affiliation(s)
- Olivier Grémy
- Laboratoire de RadioToxicologie, CEA, Université de Paris-Saclay, Bruyères le Châtel, France
| | - Sylvie Coudert
- Laboratoire de RadioToxicologie, CEA, Université de Paris-Saclay, Bruyères le Châtel, France
| | - Daniel Renault
- Laboratoire de RadioToxicologie, CEA, Université de Paris-Saclay, Bruyères le Châtel, France
| | - Laurent Miccoli
- Laboratoire de RadioToxicologie, CEA, Université de Paris-Saclay, Bruyères le Châtel, France
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Grémy O, Laurent D, Coudert S, Griffiths NM, Miccoli L. Decorporation of Pu/Am Actinides by Chelation Therapy: New Arguments in Favor of an Intracellular Component of DTPA Action. Radiat Res 2016; 185:568-79. [PMID: 27195610 DOI: 10.1667/rr14193.1] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Diethylenetriaminepentaacetic acid (DTPA) is currently still the only known chelating drug that can be used for decorporation of internalized plutonium (Pu) and americium (Am). It is generally assumed that chelation occurs only in biological fluids, thus preventing Pu/Am deposition in target tissues. We postulate that actinide chelation may also occur inside cells by a mechanism called "intracellular chelation". To test this hypothesis, rats were given DTPA either prior to (termed "prophylactic" treatment) or belatedly after (termed "delayed" treatment) Pu/Am injection. DTPA decorporation efficacy was systematically tested for both plutonium and americium. Both prophylactic and delayed DTPA elicited marked decreases in liver Pu/Am. These results can be explained by chelation within subcellular compartments where DTPA efficacy increased as a function of a favorable intracellular DTPA-to-actinide molar ratio. The efficacy of intracellular chelation of liver actinides decreased with the delay of treatment. This is probably explained by progressive actinide binding to the high-affinity ligand ferritin followed by migration to lysosomes. Intracellular chelation was reduced as the gap between prophylactic treatment and contamination increased. This may be explained by the reduction of the intracellular DTPA pool, which declined exponentially with time. Skeletal Pu/Am was also reduced by prophylactic and delayed DTPA treatments. This decorporation of bone actinides may mainly result from extracellular chelation on bone surfaces. This work provides converging evidence for the involvement of an intracellular component of DTPA action in the decorporation process. These results may help to improve the interpretation of biological data from DTPA-treated contamination cases and could be useful to model DTPA therapy regimens.
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Affiliation(s)
- Olivier Grémy
- CEA/DSV/IRCM/Laboratoire de RadioToxicologie, Bruyères-le-Châtel, 91297 Arpajon cedex, France
| | - David Laurent
- CEA/DSV/IRCM/Laboratoire de RadioToxicologie, Bruyères-le-Châtel, 91297 Arpajon cedex, France
| | - Sylvie Coudert
- CEA/DSV/IRCM/Laboratoire de RadioToxicologie, Bruyères-le-Châtel, 91297 Arpajon cedex, France
| | - Nina M Griffiths
- CEA/DSV/IRCM/Laboratoire de RadioToxicologie, Bruyères-le-Châtel, 91297 Arpajon cedex, France
| | - Laurent Miccoli
- CEA/DSV/IRCM/Laboratoire de RadioToxicologie, Bruyères-le-Châtel, 91297 Arpajon cedex, France
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CATSCH A, LE DK, CHAMBAULT D. Evaluation of the Efficacy of Different Metal Chelates of DTPA in Removing Internally-deposited Radionuclides. ACTA ACUST UNITED AC 2009; 8:35-43. [PMID: 14190705 DOI: 10.1080/09553006414550031] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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MARKLEY JF, ROSENTHAL MW, LINDENBAUM A. Distribution and Removal of Monomeric and Polymeric Plutonium in Rats and Mice. ACTA ACUST UNITED AC 2009; 8:271-8. [PMID: 14234753 DOI: 10.1080/09553006414550281] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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MARKLEY JF. Removal of Polymeric Plutonium from Mice by Combined Therapy with the Calcium Chelate and Penta-ethyl Ester of DTPA. ACTA ACUST UNITED AC 2009; 7:405-7. [PMID: 14112208 DOI: 10.1080/09553006314551351] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Gorden AEV, Xu J, Raymond KN, Durbin P. Rational Design of Sequestering Agents for Plutonium and Other Actinides. Chem Rev 2003; 103:4207-82. [PMID: 14611263 DOI: 10.1021/cr990114x] [Citation(s) in RCA: 428] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Anne E V Gorden
- Department of Chemistry, University of California, Berkeley, California 94720, USA
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14
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Abstract
This note is the brief history of a word. Decorporation is a scientific term known to health physicists who have an interest in the removal of internally deposited radionuclides from the body after an accidental or inadvertent intake. Although the word decorporation appears many times in the radiation protection literature, it was only recently accepted by the editors of the Oxford English Dictionary as an entry for their latest edition.
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Affiliation(s)
- D R Fisher
- Hanford Radioisotopes and Medical Sciences Program, Pacific Northwest National Laboratory, Richland, WA 99352, USA.
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Abstract
An examination of the studies on therapeutic chelating agents that have been carried out during the last decade reveals that extensive efforts have been made to develop compounds superior to those previously available for the treatment of acute and chronic intoxication by many metals. These metals include primarily iron, plutonium, cadmium, lead, and arsenic, but also many other elements for which acute and chronic intoxication is less common. These studies have revealed the importance of several additional factors of importance in the design of such compounds and have led to many new compounds of considerable clinical promise. An additional development has been the introduction of previously developed chelating agents for use with certain metals on a broader scale.
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Affiliation(s)
- M M Jones
- Department of Chemistry, Vanderbilt University, Nashville, TN 37235
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17
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Harrison JD, David AJ, Stather JW. Experimental studies of the translocation of plutonium from simulated wound sites in the rat. INTERNATIONAL JOURNAL OF RADIATION BIOLOGY AND RELATED STUDIES IN PHYSICS, CHEMISTRY, AND MEDICINE 1978; 33:457-72. [PMID: 306979 DOI: 10.1080/09553007814550371] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Wound contamination with plutonium was simulated in rats by injection into either muscle or subcutaneous tissue. The distribution after the injection of plutonium nitrate indicated that: (i) clearance from the contaminated tissue was due mainly to the movement of soluble complexes of plutonium, principally to the skeleton and liver, but also involved slower movement of polymerized, particulate plutonium to lymph nodes; (ii) clearance of soluble plutonium, and hence the overall state of clearance, was dependent on the tissue fluid flow through the contiminated tissue and the mass of plutonium deposited; (iii) lymphatic clearance of particulate plutonium resulted in the release of some particles into the circulation and subsequent uptake by the liver. Intramuscular deposition of small plutonium dioxide particles (approximately 1 nm in diameter) resulted in a greater rate of clearance of plutonium than deposition of the nitrate. Although the solubility of these particles was evident from the level of skeletal uptake of plutonium, a high level of excretion indicated that some plutonium was filtered into the urine in an undissolved form.
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Catsch A, Harmuth-Hoene AE. Pharmacology and therapeutic applications of agents used in heavy metal poisoning. ACTA ACUST UNITED AC 1976. [DOI: 10.1016/0362-5478(76)90011-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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19
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Toxicology of Plutonium. ACTA ACUST UNITED AC 1974. [DOI: 10.1016/b978-0-12-035404-7.50012-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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20
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Rahman YE, Rosenthal MW, Cerny EA. Intracellular plutonium: removal by liposome-encapsulated chelating agent. Science 1973; 180:300-2. [PMID: 4633691 DOI: 10.1126/science.180.4083.300] [Citation(s) in RCA: 113] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Chelating agents, such as ethylenediaminetetraacetic acid (EDTA) and diethylenetriaminepentaacetic acid (DTPA) were successfully encapsulated within lipid spherules (that is, liposomes). Encapsutlated [(14)C]EDTA, given intravenously to mice, was retained longer in tissues that nonencapsulated [(14)C]EDTA. Encapsulated DTPA, given to mice 3 days after pluttonium injection, removed an additional fraction of plutonium in the liver, presumably intracellular, not available to nonencapslulated DTPA. It also further increased urinary excretion of plutonium. Introduction of chelating agents into cells by liposomal encapsulation is a promising new approach to the treatment of metal poisoning
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Abstract
Intracellular incorporation of polymeric plutonium injected into mice was demonstrated in liver and spleen by electron-microscopic auto-radiography. The observations are not inconsistent with other evidence indicating the association of plutonium with lysosomal components. Early results with a quantitative electron-microscopic technique may lead to microdosimetry of cells and cellular components.
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