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Increased deposition of uranium in the bones of vitellogenic male Japanese quail. Effect of estradiol-17 beta on the distribution of uranium (VI), thorium (IV), gadolinium (III), and calcium (II).

Japanese quail were given, intramuscularly, either 16-mumol estradiol-17 beta (E2) in .25-ml ethanol solution/100 g body weight or .25 ml ethanol/100 g. Four days later, these quail were given, intravenously, 1.5-mumol UO2(NO3)2, Th(NO3)4, GdCl3 (153Gd-labeled) or CaCl2 (47Ca-labeled)/.15 ml .03 N HCl solution/100 g. The distribution of uranium among selected tissues was markedly different than for thorium or gadolinium and was approximately the same as for calcium. For example, 18 hr after giving the metal ions to the quail, the mean uranium content of the femora + tibiotarsi of E2-treated males was 15.4 +/- 1.3% (SE; n = 12) vs. 3.07 +/- .59% (12; P less than .001) for the control males. Similarly, 18 hr after giving calcium, the femora + tibiotarsi of E2-treated males had accumulated 20.8 +/- 1.5% (4) of the label vs. 9.94 +/- .46% (4; P less than .001) for controls. The livers of E2-treated males had 41.9 +/- 8.5% (4) of the thorium by 18 hr vs. 90.9 +/- 7.1% (4; P less than .01) for the controls, or 34.3 +/- 3.1% (8) of the gadolinium vs. 68.9 +/- 3.4% (8; P less than .001) for controls. The 18-hr accumulation of calcium in the femora + tibiotarsi of the E2-treated females was 18.0 +/- 1.1% (4) vs. 10.7 +/- 1.9% (4; P less than .05) for the controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Complexation equilibria and spectrophotometric determination of thorium(IV) with Lawsone.

The complex equilibria of Th4+ with Lawsone (2-hydroxy-1,4-naphthoquinone, LAS) were studied spectrophotometrically in 40% (v/v) ethanol water at 25 degrees C and an ionic strength of 0.1 M (NaClO4). The absorbance graphs were analysed to demonstrate and characterize the complex forming equilibria. A simple, rapid, selective and sensitive method for the spectrophotometric determination of trace amounts of thorium(IV) is developed. The complex formed at pH 2.1-3.6 (epsilon = 0.27 x 10(4) cm2 mol-1, at lambda = 440 nm) allows the determination of 5.8-32 micrograms/ml thorium. The effect of interferences was studied.

Absorption↗

Thorium and actinium polyphosphonate compounds as bone-seeking alpha particle-emitting agents.

The present study explores the use of alpha-particle-emitting, bone-seeking agents as candidates for targeted radiotherapy. Actinium and thorium 1,4,7,10 tetraazacyclododecane N,N',N'',N''' 1,4,7,10-tetra(methylene) phosphonic acid (DOTMP) and thorium-diethylene triamine N,N',N'' penta(methylene) phosphonic acid (DTMP) were prepared and their biodistribution evaluated in conventional Balb/C mice at four hours after injection. All three bone-seeking agents showed a high uptake in bone and a low uptake in soft tissues. Among the soft tissue organs, only kidney had a relatively high uptake. The femur/kidney ratios for 227Th-DTMP, 228-Ac-DOTMP and 227Th-DOTMP were 14.2, 7.6 and 6.0, respectively. A higher liver uptake of 228Ac-DOTMP was seen than for 227Th-DTMP and 227Th-DOTMP. This suggests that some demetallation of the 228Ac-DOTMP complex had occurred. The results indicate that 225Ac-DOTMP, 227Th-DOTMP and 227Th-DTMP have promising properties as potential therapeutic bone-seeking agents.

Actinium↗

Malignant fibrous histiocytoma. Induced by thorium.

Thorium dioxide is a deleterious substance that was employed as a vascular contrast medium during the early 20th century. Our report entails a unique neoplastic complication of thorium administration.

Adolescent↗

Interactions of thorium and cerium with adenine nucleotides.

The present study demonstrates an effect of the actinide, Thorium (Th), and the lanthanide, Cerium (Ce), on the non-enzymatic hydrolysis of adenine and guanine nucleotides. Thorium was found to be a more effective catalyst of the reaction than Cerium. Further, both the elements promoted the binding of Creatine kinase (CK) to Cibacron blue F3 GA, the substrate analogue of the enzyme, even in the absence of Mg2+, the physiological cofactor. These observations imply that toxic heavy metals can mimic the functional effects of the essential elements despite differences in their physicochemical properties.

Adenine Nucleotides↗

Demonstration of iron and thorium in autopsy tissues by X-ray microanalysis.

We performed x-ray microanalysis of autopsy specimens using a scanning-transmission electron microscopy mode. Tissues were obtained at necropsy from a patient with history of angiography using thorium dioxide and from a patient with hemochromatosis. X-ray microanalysis confirmed the presence of thorium and iron in their respective tissues. Effects of staining reagents were examined.

Angiography↗

Cervical thorium dioxide granuloma ('thorotrastoma').

An elderly woman had an expanding cervical mass that entrapped and compressed the adjacent cranial nerves, blood vessels, and muscles. The mass was dense on radiographs, extended from the skull base to low neck in the prevertebral and parapharyngeal tissues, and showed mixed intensity on MR. A previous direct carotid arteriogram with thorium dioxide as the contrast agent suggested the histologically proved diagnosis of a cervical thorium dioxide granuloma ("thorotrastoma").

Diagnosis, Differential↗

Hodgkin's disease following thorium dioxide angiography.

Hodgkin's disease occurred in a 53-year-old man who, 25 years previously, had undergone cerebral angiography, for which thorium dioxide suspension (Thorotrast) was used. Deposits of throium dioxide were noted in reticuloendothelial cells in various locations. An association between thorium dioxide administration and the subsequent development of malignant tumours and neoplastic hematologic disorders has previously been reported.

Autoradiography↗

Condensation reaction in the bandpass reaction cell improves sensitivity for uranium, thorium, neodymium and praseodymium measurements.

Condensation reactions in the bandpass reaction cell or dynamic reaction cell (DRC) were used for the determination of actinides and lanthanides such as uranium, thorium, neodymium and praseodymium. These elements react with oxygen reagent gas in the dynamic reaction cell of the ELAN DRC II instrument to give mono- and/or dioxo cationic species (UO(2)+, ThO+, NdO+ and PrO+, respectively). Increasing the oxygen flow rate in the dynamic reaction cell leads to the rapid decrease of the singly charged metal ions accompanied by the fast increase in the intensity of the oxide ion. This phenomenon is used to improve considerably the sensitivity of ICP-MS instruments equipped with a dynamic reaction cell for actinides and lanthanides. Estimated detection limits (EDL) obtained in this work for uranium, thorium, neodymium-144 and praseodymium are 0.022, 1.0, 0.045, and 0.10 ng L(-1), respectively. The detection limit for uranium measured in the standard (vented) mode of an ELAN DRC II was found to be 0.22 ng L(-1), which is an order of magnitude higher compared to the pressurized mode.

Journal Article↗

Investigation in hydrated thorium phosphates by NMR I-relation proton phosphorus.

The relations between (1)H and (31)P nuclei are investigated by multinuclear and multidimensional nuclear magnetic resonance (NMR) spectroscopy in order to obtain structural information along the transformation of the thorium phosphate hydrogen phosphate hydrate (TPHPH) into the thorium phosphate diphosphate (TPD) when heating. The raw sample obtained at 120 degrees C was heated at 300, 400, 600, 800 or 1100 degrees C and then studied at room temperature. Single acquisition on (1)H and (31)P nuclei, cross-polarization (CP) at the magical angle spinning, Lee-Golburg homonuclear decoupling in two-dimensional experiments, rotational echo double resonance (REDOR and CP-REDOR) and heteronuclear correlation (HETCOR) were performed. These experiments contribute to evidence the differences between the raw sample and that heated. Indeed, above 300 degrees C, hydrogen phosphate groups (HPO(4)) are completely condensed as diphosphate entities (P(2)O(7)). These results confirm that the TPHPH is successively transformed into a low-temperature form of the TPD (called alpha-TPD), then into its well-known beta-form above 950 degrees C.

Journal Article↗

A method for the rapid radiochemical analysis of uranium and thorium isotopes in impure carbonates.

A simple method combining solvent extraction and electrodeposition procedures is described for the determination of the isotopic composition and content of uranium and thorium in travertine samples. The actinide elements are extracted with diethyl ether from a calcium nitrate solution. The isolation of the elements and the alpha source preparation are performed in two steps after the sample digestion. The acid leaching of samples is performed using both partial and total dissolution methods. High recoveries of both uranium and thorium and good alpha-spectra are obtained with both partial and total dissolution methods.

Journal Article↗

Structure of the Aqua Ions and Fluoride Complexes of Uranium(IV) and Thorium(IV) in Aqueous Solution an EXAFS Study.

The structures of aqueous M(4+)(aq) and MF(3+)(aq), where M is uranium(IV) or thorium(IV), have been determined by L(III) edge EXAFS using data from solutions of 1.5 M HClO(4) in which the M(IV) concentrations ranged from 0.03 to 0.3 M. A least-squares refinement of the data for the aqua ions indicated 10.8 +/- 0.5 water molecules in the first hydration sphere of both ions and M-O bond distances for U(IV) and Th(IV) of 2.42 +/- 0.01 and 2.45 +/- 0.01 Å, respectively. By considering both previous structure information and the EXAFS data, we selected N = 10 +/- 1 as the most likely coordination number of both M(IV) aqua ions. EXAFS measurements from acidic aqueous uranium(IV) and thorium(IV) solutions containing fluoride show that large changes in the first coordination sphere occur. The experimental data indicates an asymmetrical distribution of the distances, probably as a result of differing M-F and M-O bond lengths. These can be described by a model that contains two different bond distances, one M-F distance at 2.10 Å and one M-O distance at 2.45 Å for U(IV); for Th(IV), the corresponding distances are 2.14 and 2.48 Å. The total coordination number in this model is unchanged from the aqua ions, i.e., 10 +/- 1.

Journal Article↗

Experimental and theoretical studies of the products of laser-ablated thorium atom reactions with H2O in excess argon.

Reactions of laser-ablated Th atoms with H2O during condensation in excess argon have formed a variety of intriguing new Th, H, O species. Infrared absorptions at 1406.0 and 842.6 cm-1 are assigned to the H-Th and Th=O stretching vibrations of HThO. Absorptions at 1397.2, 1352.4, and 822.8 cm-1 are assigned to symmetric H-Th-H, antisymmetric H-Th-H, and Th=O stretching vibrations of the major primary reaction product H2ThO. Thorium monoxide (ThO) produced in the reaction inserts into H2O to form HThO(OH), which absorbs at 1341.0, 804.0, and 542.6 cm-1. Both HThO(OH) and ThO2 add another H2O molecule to give HTh(OH)3 and OTh(OH)2, respectively. Weaker thorium hydride (ThH1(-4)) absorptions were also observed. Relativistic DFT and ab initio calculations were performed on all proposed molecules and other possible isomers. The good agreement between experimental and calculated vibrational frequencies, relative absorption intensities, and isotopic shifts provides support for these first identifications of Th, H, O molecular species.

Journal Article↗

Protactinium-231 and thorium-230 abundances and high scavenging rates in the western arctic ocean

The Canadian Basin of the Arctic Ocean, largely ice covered and isolated from deep contact with the more dynamic Eurasian Basin by the Lomonosov Ridge, has historically been considered an area of low productivity and particle flux and sluggish circulation. High-sensitivity mass-spectrometric measurements of the naturally occurring radionuclides protactinium-231 and thorium-230 in the deep Canada Basin and on the adjacent shelf indicate high particle fluxes and scavenging rates in this region. The thorium-232 data suggest that offshore advection of particulate material from the shelves contributes to scavenging of reactive materials in areas of permanent ice cover.

Journal Article↗

Rapid non-destructive quantitative estimation of urania/thoria in mixed thorium uranium di-oxide pellets by high-resolution gamma-ray spectrometry.

A non-destructive technique using high-resolution gamma-ray spectrometry has been standardised for quantitative estimation of uranium/thorium in mixed (ThO2-UO2) fuel pellets of varying composition. Four gamma energies were selected; two each from the uranium and thorium series and the time of counting has been optimised. This technique can be used for rapid estimation of U/Th percentage in a large number of mixed fuel pellets from a production campaign.

Radiation Monitoring↗

Gametogenic count and histopathological effect of thorium nitrate and uranyl nitrate on mice testes.

Daily intraperitoneal administration of aqueous solution of 0.05 m mole/100 g b. wt. of uranyl nitrate and thorium nitrate has been observed for 7 days. Marked reduction in the seminiferous tubule diameter and gametogenic count was observed. Signs of testicular necrosis, exfoliation of germ cells, and karyolysis and karyorrhexis were seen in most of the tutubles. Mononucleate and polynucleate giant cells were also observed indicating prolonged pathological condition.

Animals↗

Partition of thorium between organs of monkeys injected with thorotrast: implications for alpha-particle dosimetry.

Risk estimates for alpha-particle-induced malignancies have been based mainly on studies of Thorotrast patients, but certain aspects of its deposition in the body have been at issue: the partition between the liver, spleen and red bone marrow, and the deposition at lower concentrations in other organs, such as muscle and fat, which may contribute to the risk. To supplement the existing data for humans, thorium concentrations were measured in the organs of two female monkeys 3-4 years after injection with Thorotrast. Relative deposits (liver:spleen:red bone marrow) were 54:6:41 and 75:4:21, in better agreement with the most recent observations in Thorotrast patients than with previous reports. Whereas the human testis had ranked among intermediate-level organs such as the adrenal glands and pancreas, the ovary of the monkey was among the organs with the lowest concentrations. The data suggest that risk factors for induction of malignancies by alpha-particle irradiation should be re-examined.

Animals↗