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Effects of ethylenediaminetetraacetic acid (EDTA) and diethylenetriaminepentaacetic acid (DTPA) derivatives on penetration of ytterbium-169 and cerium-144 into the rat offspring.

Effects of ethylenediaminetetraacetic acid (EDTA) and diethylenetriaminepentaacetic acid (DTPA) derivatives on penetration of ytterbium-169 and cerium-144 into the rat offspring. Acta Physiol. Pol., 1976, 27 (2): 175-181. Penetration of radioactive ytterbium-169 and cerium-144 into fetuses was determined at the end of pregnancy and penetration into the organism of suckling rats was studied during feeding with the milk of exposed mothers when EDTA or DTPA derivatives were being administered. Injection of ytterbium-169 as a complex with EDTA or DTPA or injection of Na2Ca EDTA or Na3Ca DTPA 1h after administration of cerium-144 to mothers reduced penetration of both radionuclides into offsprings in relation to the animals receiving no complex compounds. It was observed that the action of DTPA was stronger than that of EDTA. Passage of ytterbium with milk and across the placenta was greater than the passage of cerium.

Animals

The embryotoxicity of ytterbium chloride in golden hamsters.

Two experiments were performed to assess the embryotoxicity of intravenously administered ytterbium chloride in golden hamsters: (1) 50, 75, 100, or 150 mg/kg ytterbium chloride were injected early on the 8th gestation day; (2) 100 mg/kg ytterbium chloride were administered at 4 different times during the critical period of organogenesis in this species (7th day, 4 PM; 8th day, 8 AM or 4 PM; 9th day, 8 AM). The pregnant females were killed on the 12th, 14th, or 15th gestation day and the frequency of resorptions was determined, and surviving offspring were studied for the presence of external and internal malformations as well as skeletal damage. Relatively few externally visible malformations and no significant internal malformations were produced. Damage to the skeletal system included fused and supernumerary ribs, and many different sites of poor ossification. Maximal susceptibility to these effects occurred on the 8th day.

Abnormalities, Drug-Induced

[Value of isotope study with ytterbium-169 citrate in the diagnosis of pulmonary opacities of cancerous nature].

Out of 60 observations, the authors deduct the value of the isotopic study with Ytterbium169 citrate in the diagnosis of cancerous pulmonary opacities. Ytterbium169 is a radiolanthanide with a period of 32 days. Patients receive intravenously 500 muCi of Ytterbium169 citrate. Recordings are made on the 2nd, 7th and 14th day. Valuable information on the data of the fixation rate on the 2nd and 14th day can be obtained from drawing a curve of fixation. As shown by the dosimetric study the radioactive pollution is minimal; nevertheless the dose of irradiation should not be underestimated and not recommended for young patients. Reliability of the examination is great: the percentage of true positive results is satisfactory (87%) and above all the percentage of false positive results (7.7%) much below that of other isotopes (30-40%). Results are excellent for peripheral opacities which escape the usual diagnostic mean. The main failure of the examination is the relatively frequent lack of fixation, not prejudicial in itself as it has no diagnostic value. Indications and limits of this examination are drawn from this study.

Age Factors

Clearance of calcium pyrophosphate dihydrate crystals in vivo. I. Studies using 169Yb labeled triclinic crystals.

Synthetic triclinic calcium pyrophosphate dihydrate crystals were uniformly trace-labeled with Ytterbium-169 (169Yb), a pure gamma-emitting isotope with a halflife of 31 days. The solubility of the labeled crystals was similar to that of cold synthetic crystals. The clearance rate of labeled sterile crystals, sieved to obtain the desired size, was determined after injection of microgram quantities into 4 arthritic huuman and 3 normal adult rabbit joints and corrected by the observed rate of clearance of free 169Yb. The derived rate constants were then used to calculate the time required for half of the injected dose of CPPD to be cleared from the joint. Crystal clearance was found in all instances. Crystal removal from normal rabbit joints was much more rapid than from the much larger human arthritic joints and was inversely proportional to the size of the crystals injected.

Animals

[Postural scintimyelography of the cervical spine (author's transl)].

This study discusses the clinical validity of 101 postural scintimyelograms as a screening method for cervical myelopathy. The RIHSA or Ytterbium isotope-examination are not an extra burden to the patient if the radiopharmacon is introduced into the dural sac following Queckenstedt's test. If there is a normal rise and fall of CSF pressure after bilateral jugular compression and postural scintimyelography is judged normal as well, a cervical subarachnoid obstruction may be excluded. If both examinations yield pathological results an obstructive process in the cervical spinal canal is made certain; and in cases of spondylotic myelopathy a positive contrast myelogrpahy may thus be superfluous. If the results of these two examinations are contradictory then further neuroradiolocal studies are indicated.

Cerebrospinal Fluid

Lanthanide markers in a single sample for nutrient studies in humans.

Multiple Lanthanide markers were used to develop procedures for determinations of intake and apparent utilization of four nutrients using data from fecal analysis and known concentrations of markers in nutrients. Terbium oxide was given as the intake marker. All foods contained the other non-absorbed markers, each marker in direct proportion to the amount of a specific nutrient in each food. Nutrient markers were oxides of samarium, scandium, ytterbium, and europium. Fecal collection and subsequent analysis of nutrients and markers were completed. Fecal marker concentration stabilized 2 days following initiation of the marker regime. Thus, after 3 days, a single grab sample could be utilized to analyze for nutrient utilization. The ratio of nutrient marker proportional to nutrient and intake to nutrient excretion provides the data for the calculation of apparent utilization for as many nutrients as nutrient markers incorporated into the food. When direct and marker methods of determining nutrient intake and apparent utilization were compared, no significant differences were found for gross energy, fat, protein, and calcium.

Adult

Reduction of patient exposure by use of heavy elements as radiation filters in diagnostic radiology.

The effect on patient exposure of x-ray filters made of heavy elements has been studied in excretory urography and lumbar spine examinations. Several elements with atomic numbers between 62 and 74 were tested in experiments using radiographic phantoms and in patient studies. A holmium filter reduced skin exposure by more than 50% in excretory urography. Similar results were obtained with ytterbium and tungsten in lumbar spine studies.

Aluminum

[Radioisotopes used in the diagnosis of bone diseases].

The radiopharmacons produced in Hungary and suitable for the demonstration of reactive bone alterations are discussed by the authors. These pharmacons are the following: 85ScCl2=Strontiumchloride, 153Sm-EDTA=Samarium ethylendiamintetraacetate, 169Yb-citrate=Ytterbium-citrate, 99mTc-HEDSPA=Technetium-hydroxy-ethylene-diphosphonate, 99mTc-pyrophosphate. The scintigraphic pictures obtained by the use of these radiopharmacons are presented. On the basis of their experimental examinations the numerous advantages of the use of 99mTc-HEDSPA are pointed out and the possibilities are outlines, which are to be obtained in the detection of occult bone alterations, in the examination of juvenile patients and perhaps in the case of osteotransplantation.

Bone Diseases

Distension of the operation site after posterior fossa surgery.

In 130 posterior fossa operations 6 cases of progressive distension of the operation site have been recorded and documented. The possible causes of this complication and the surgical management are discussed. Isotope studies after injection of Ytterbium 169DTPA into the underlying cyst have shown abnormal patterns in CSF circulation and absorption. All the cases have resolved after ventriculo-peritoneal shunts.

Adult

Lanthanide octaethylprophyrins: preparation, association, and interaction with axial ligands.

The synthesis of virtually all the lanthanide octaethylporphyrin complexes have been achieved by heating appropriate anhydrous lanthanide halide and octaethylporphyrin in imidazole melt at 210 degrees C for two hours. The lighter lanthanide porphyrin complexes are very susceptible to hydrolysis, the middle lanthanide porphyrin complexes are moderately stable, and the heavier lanthanide porphyrin complexes are relatively more stable to hydrolysis. Two out of four lanthanide porphyrin complexes studied in detail, namely ytterbium and lutetium octaethylporphyrins, aggregate in benzene and the Soret bands in their absorption spectra are about 6 nm shifted to higher energies upon a hundred-fold increase in their concentrations. The aggregations of these lanthanide porphyrin complexes in non-coordinating solvents have been further verified by 1H NMR spectral studies. This spectral behavior can be interpreted qualitatively in terms of the model of the molecular exciton interactions with stacking of at least two prophyrins. A dimeric structure of these lanthanide porphyrin complexes has been proposed on the basis of geometrical considerations. On the contrary, the europium and gadolinium octaethylporphyrins associate very weakly in benzene in the concentration range studied. All four lanthanide porphyrin complexes interact with pyridine and piperidine, and the Soret bands in their absorption spectra are about 8 nm shifted to low energies as compared with their values in pure benzene.

Ligands

Hemodynamics during superficial thiopental anesthesia in the dog.

Radioactive microspheres, labeled withe ytterbium (169Yb), strontium (85Sr) and cerium (141Ce) were used in an investigation of the cardiovascular response to superficial thiopental anesthesia. The course was followed for 90 min and measurements were carried out 30, 60 and 90 min, respectively. Between 30 and 60 min of anesthesia there was a slight decrease in cardiac output and left ventricular work. The blood flow was reduced to the lungs, kidneys and the liver. Between 60 and 90 min there were, except for the coeliac artery and total liver, no further changes, which indicated a circulatory steady state.

Anesthesia, Intravenous

Diaphragmatic blood flow at various levels of ventilation in the rabbit.

Diaphragmatic and renal blood flow were measured with Ytterbium-169 and Scandium 46 labelled 15 micron microspheres in sodium pentobarbitone anesthetized rabbits. The first measurement was performed during spontaneous breathing of air and the second measurement after 15 min of breathing 2-6% carbon dioxide in oxygen. The lung ventilation as well as the diaphragmatic blood flow increased significantly during breathing of the carbon dioxide-oxygen mixture. Arterial blood pressure and renal blood flow were not significantly altered by the induced hyperventilation. No significant correlation was found between the magnitude of lung ventilation and diaphragmatic blood flow. The results of the present study indicate that consecutive measurements of diaphragmatic blood flow with radioactive microspheres at various levels of breathing effort is an appropriate method for further exploration of the relationship between diaphragmatic perfusion and working performance.

Animals

Neutron activation analysis of the rare earth elements in Nasu hot springs.

Eleven rare earth elements (lanthanum, cerium, neodymium, samarium, europium, gadolinium, terbium, holmium, thulium, ytterbium and lutetium) in hot spring waters and sinter deposits in the Nasu area were determined by the neutron activation method. The rare earth elements in hot spring water were pre-concentrated in ferric hydroxide precipitate and neutron-irradiated. The rare earth elements were chemically separated into lighter and heavier groups and the activity of each group was measured with a Ge(Li) detector. Distribution of the rare earth elements between the hot spring water and the sinter deposit was also discussed.

Activation Analysis

[Effect of gum guar in diet on nitrogen balance, protein metabolism and food transit time in rats].

The addition of 5% gum guar to a diet containing 10% casein did not change the overall N retention of young rats but induced a significant shift in the N excretion from urine to feces, resulting in a markedly decreased apparent protein digestibility. The increase in total fecal dry matter over control values accounted for only 30% of the ingested gum guar implying that 70% was absorbed, possibly after being degraded by intestinal micro-organisms. The elimination of 14C activity following oral application of 14C protein indicated an accelerated turnover of amino acids during the first 3 h. After 25 h no difference between experimental and control animals was evident with respect to 14C activity remaining in the carcass. The transit time of food, as determined by neutron activation analysis of an Ytterbium marker, was somewhat decreased in the presence of gum guar.

Amino Acids

External detection of axoplasmic flow using radionuclides.

In order to investigate the possibilities of studying the axoplasmic flow in vivo by means of radionuclide scanning 75Se-methionine was injected into the L6, L7 or S1 spinal ganglia of cats and the spread of the isotope recorded with a gamma camera. -2. After 4 hours the area of isotope distribution extended 1-2 cm cranially and caudally in the spinal cord and a further movement of 1-2 cm was noted during the following 2-5 days. -3. Scanning of removed specimens of the spinal cord, roots, ganglia and nerves confirmed the intramedullary uptake and in addition revealed an uptake in the dorsal root. Determination of the specific radioactivity showed the presence of the isotope in the ventral root and spinal nerve also, however, sufficient for scintigraphy. -4. Microautoradiographic studies with 3H-methionine demonstrated isotope uptake in axons of the dorsal roots and root entry zone of the spinal cord. Hence, the spread of the isotope was likely to have occurred by axoplasmic flow. This seems to provide a basis for further in vivo studies of this phenomenon.

Animals