Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “RADIOACTIVITY”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 397 records · Page 22Linked to original sources
PubMed2002

The PET radioligand [carbonyl-(11)C]desmethyl-WAY-100635 binds to 5-HT(1A) receptors and provides a higher radioactive signal than [carbonyl-(11)C]WAY-100635 in the human brain.

UNLABELLED: 5-Hydroxytryptamine (serotonin)-1A (5-HT(1A)) receptors are of key interest in research on the pathophysiology and treatment of psychiatric disorders. The PET radioligand [carbonyl-(11)C]WAY-100635 ((11)C-WAY), where WAY-100635 is (3)H-(N-(2-(1-(4-(2-methoxyphenyl)-1-piperazinyl)ethyl)-N-(2-pyridyl) cyclohexane-carboxamide, is commonly used for quantitation of 5-HT(1A) receptors in the human brain. The aim of this PET study was to compare (11)C-WAY with the putative metabolite and selective radioligand [carbonyl-(11)C]desmethyl-WAY-100635 ((11)C-DWAY). METHODS: A PET examination was performed on each of 5 healthy male volunteers after intravenous injection of (11)C-WAY and (11)C-DWAY on separate occasions. Radioactive metabolites in plasma were determined with high-performance liquid chromatography. The plasma metabolite--corrected input function was used in a kinetic compartment analysis. The simplified reference tissue model and peak equilibrium method, using the cerebellum as reference region, was applied for comparison of data. RESULTS: For both radioligands, the highest radioactivity was observed in the neocortex and the raphe nuclei, whereas radioactivity was low in the cerebellum. The regional binding potentials were similar for the 2 radioligands. The brain uptake was more than 2-fold higher for (11)C-DWAY than for (11)C-WAY, in part because of higher delivery (first-order rate constant K(1), 0.38 vs. 0.16). The time--activity curves were well described by a 3-compartment model for all regions, whereas uptake in the cerebellum could not be described by a 2-compartment model, supporting the existence of kinetically distinguishable nonspecific binding in the cerebellum or radioactive metabolites in the brain for both radioligands. Both radioligands were rapidly metabolized, and <10% of the radioactivity in plasma represented unchanged (11)C-WAY or (11)C-DWAY at 10 min after injection. The metabolic pattern was similar for both radioligands, with the formation of radiolabeled cyclohexanecarboxylic acid and more polar components. For (11)C-WAY, small amounts of an additional labeled metabolite comigrated with reference desmethyl-WAY-100635. CONCLUSION: The advantages of (11)C-DWAY over (11)C-WAY for research on central 5-HT(1A) receptors is supported by a significantly higher radioactivity signal at equipotent doses, providing improved imaging statistics and advantages in biomathematic modeling and the preclusion of (11)C-DWAY as a metabolite interfering with PET measurements.

Adult↗
PubMed1975

[Problems associated with the labelling of RNA with radioactive precursors in vivo (author's transl)].

The radioactivity of RNA, DNA and proteins in the liver, muscles and cerebrum of 30-day-old rats after labelling with [3H]uridine, [14C]uridine, [3H]cytidine or [3H]orotic acid was measured. It was found that after administration of [3H]uridine, the proteins were 5 - 10 times more radioactive than the RNA. After administration of [14C]uridine, the proteins were 1 - 2 times more heavily labelled than the RNA. Hydrolysis of the proteins followed by chromatography of the amino acids revealed that the protein labelling was mostly due to [3H]glutamate. In the liver, [3H]orotic acid produced very specific labelling of the RNA. The radioactivity of the proteins is very slight. However, the specific labelling of the RNA in the muscles and cerebrum is not so pronounced with this precursor. [3H]Cytidine is an ideal precursor for RNA. The labelling of protein in all three organs examined is very slight, and furthermore, the specific activity of the RNA is 10 - 20 times higher than after labelling with uridine. We were also able to show that after labelling with radioactive uridine, the method of isolation of RNA by alkaline hydrolysis gives incorrect results, because [3H]amino acids interfere with the measurement of the specific activity of the RNA. The heavy labelling of proteins by [3H]-uridine must also be taken into account in histoautoradiography, because our experiments showed that in liver, the proteins in the cell nucleus are 3 times as radioactive as the nucleic acids. The particulate components of the cytoplasm are even 20 times more radioactive than the nucleic acids.

Animals↗
PubMed1975

Intracellular formation of analogs of cyclic AMP. Studies with brain slices labeled with radioactive derivatives of adenine and adenosine.

A variety of radioactive analogs of adenine and adenosine were incubated with guinea pig cerebral cortical slices. Neither 1,N6-etheno[14C] adenosine nor 1,N6-etheno[14C] adenine were significantly incorporated into intracellular nucleotides. 2-chloro[8-3H] adenine was incorporated, but at a very low rate and conclusive evidence for the formation of intracellular radioactive 2-chloro-cyclic AMP was not obtained. N6-Benzyl[14C] adenosine was converted only to intracellular monophosphates and significant formation of radioactive N6-benzylcyclic AMP was not detected during a subsequent incubation. 2'-Deoxy-[8-14C] adenosine was converted to both intracellular radioactive 2'-deoxy-adenine nucleotides and radioactive adenine nucleotides. Stimulation of these labeled slices with a variety of agents resulted in formation of both radioactive 2'-deoxycyclic AMP and cyclic AMP. Investigation of the effect of various other compounds on uptake of adenine or adenosine suggested that certain other adenosine analogs might serve as precursors of abnormal cyclic nucleotides in intact cells.

Adenine↗
PubMed1991

[Evaluation of the tracheobronchial clearance in patients with chronic bronchial infections by an integrated system using radioactive aerosol inhalation scintigraphy].

It is widely accepted that the impairment of tracheobronchial clearance (TBC) are closely related to the development and the progression of chronic bronchial infections. We investigated TBC in patients with chronic bronchial infections (bronchiectasis; 11 cases, diffuse panbronchiolitis; 9 cases and primary ciliary dyskinesia; 3 cases) and also in 6 healthy subjects by a radioactive aerosol (99mTc-human serum albumin, 4.4 +/- 1.4 microns in diameter) inhalation scintigraphy with cough control in order to elucidate the relationships between impaired TBC and chronic bronchial infections. All subjects were not current smokers. After 4-minutes inhalation of radioactive aerosols (tidal volume: 500 ml x 20/min.), radioactivities in whole right lung were measured every 20 seconds for 2 hours serially and then measured at the time of 6 and 24 hours after inhalation. Immediately after the serial recording for 2 hours, single photon emission computed tomography (SPECT) was performed to assess the deposition pattern of radioactive aerosols. During the first 2 hours, all the subjects were instructed to avoid coughing as much as possible to evaluate the mucociliary clearance without cough effect. And then the subjects were allowed to cough between 2 and 24 hours after inhalation. All radiation counts were corrected for background radiation and physical decay of 99mTc. Because it is considered that the deposited aerosols are eliminated much more slowly in alveoli (biological half life: several months) than in airways (biological half life: several hours), the radioactivity remaining at the time of 24 hours was defined as alveolar deposition (ALV). Initial bronchial deposition (Br0) was defined as initial whole lung deposition (L0) minus ALV. We evaluated the TBC with following parameters; 1) Br0/L0 (%):ratio of initial bronchial deposition to initial lung (bronchial and alveolar) deposition. 2) Br2/Br0 (%), Br6/Br0 (%):bronchial retention ratio; the ratio of bronchial deposition at the time of 2 and 6 hours after inhalation to initial bronchial deposition, respectively. 3) TMV (mm/min.):tracheal mucus velocity (rate of shift of radioactive bolus on tracheal mucosa), which was measured during the period of first 2 hours under prohibition of cough. The patients (23 cases) were divided into two groups with regards to cough control for the first two hours of the scintigraphy:cough-controlled group (19 cases) and cough-uncontrolled group (4 cases). The cough-controlled group was subdivided into two subgroups (group A and group B) according to Br0/L0:group A less than 47.9% (mean + SD of Br0/L0 in healthy control) less than or equal to group B.(ABSTRACT TRUNCATED AT 400 WORDS)

Administration, Inhalation↗
PubMed1990

Hemodynamic changes after hepatectomy in rats studied with radioactive microspheres.

It has been difficult to measure hepatic arterial blood flow and portal venous flow simultaneously, especially in small animals. Radioactive microspheres were used in this experiment to quantitate splanchnic hemodynamics after hepatectomy in rats. With a reference sample technique, a certain amount of radioactive microspheres was injected into the left ventricle. The reference sample was withdrawn from the femoral artery at a constant rate. The animal was killed with a bolus of saturated KCl. The kidneys and splanchnic organs were removed and weighed. The radioactivity of each organ was determined using a gamma scintillation counter. Organ blood flow was calculated by the following formula: [formula: see text] Immediately after partial hepatectomy, a decreased cardiac index from 32.31 +/- 10.12 to 23.44 +/- 3.21 ml/(min x 100g body weight) (p less than 0.05), decreased hepatic arterial blood flow from 0.40 +/- 0.12 to 0.33 +/- 0.03 ml/(min x g liver) (p less than 0.05), increased portal venous inflow from 0.90 +/- 0.30 to 2.20 +/- 0.26 ml/(min x g liver) (p less than 0.05) and increased total hepatic blood flow from 1.30 +/- 0.39 to 2.53 +/- 0.26 ml/(min x g liver) (p less than 0.005) were observed. With an intrasplenic injection of an additional amount of radioactive microspheres, the ratio of lung/(lung + liver) radioactivities indicated the degree of portal systemic shunt (PSS). Though the portal pressure was elevated after hepatectomy (8.80 +/- 0.7 vs 11.9 +/- 1.7 cm H2O, p greater than 0.05), the extent of PSS was negligible (0.02 +/- 0.01% vs 0.03 +/- 0.01%, p greater than 0.05). The radioactive microspheres with the reference sample technique is a simple, rapid, reliable and reproducible method for investigating the hemodynamic changes following partial hepatectomy.

Animals↗
PubMed1990

[The effect of potassium iodide on the pharmacokinetics of radioactive iodine-labelled antibodies].

Radioactive iodine-labeled rabbit antibodies to beta 1-MA antigen (the marker of human colon cancer) were injected iv to BALB/c mice as well as to nude mice with xenografts of various human tumors. Preparations of iodinated antibodies contained an admixture of protein-unbound radionuclide 2-4% of total radioactivity. Part of the recipient animals were given per os 0.1% solution of KI to block the thyroid from radioactive iodine. A comparative study was made of the distribution of radioactivity in the tissues of recipients in the time course of 7 days. The thyroid of nude mice with tumors was shown to uptake much more radioactivity than that of immunologically intact mice. In addition to its protective effect of the thyroid from radioactive iodine, KI also enhanced the excretion of the preparation of labeled antibodies. Possible mechanisms of the revealed phenomena were analyzed.

Animals↗
PubMedDate not supplied

Studies on disposition and metabolism of tolmetin, a new anti-inflammatory agent, in rats and mice. I. Absorption, distribution, and excrection of [14C]tolmetin radioactivity.

[14C]Tolmetin was rapidly and almost completely absorbed in both rats and mice. The major portion of the drug was shown to be absorbed from the upper part of the duodenum, and a small portion from the stomach. Tissue levels of radioactivity comparable to blood levels were found only in liver and kidney, and other tissue levels were lower than those in blood, possibly because of the considerable plasma protein binding of the drug. Radioactivity disappeared from most tissues at rates similar to that from blood, and no appreciable radioactivity was found in rat and mouse tissues 24 hr after dosing. Correspondingly, radioactivity was excreted mostly in urine within this time period. Mouse fetuses contained significantly less radioactivity than did maternal tissues in autoradiography. No significant differences were found in absorption, distribution, and excretion of radioactivity when single or five consecutive daily doses of [14C]tolmetin were administered to rats.

Animals↗
PubMed1986

The late effect of subtotal thyroidectomy and radioactive iodine therapy on calcitonin secretion and bone mineral density in women treated for Graves' disease.

This study was designed to evaluate the effect of subtotal thyroidectomy and/or radioactive iodine therapy on plasma immunocalcitonin (iCT) levels and bone densities in patients treated for Graves' disease. Forty-eight women whose ages ranged from 29 to 79 years (mean, 55 years) were evaluated. All were at least 10 years beyond treatment. Fourteen patients had undergone subtotal thyroidectomy, 22 had received radioactive iodine therapy, and 12 had received both. Serum calcitonin levels were measured with the patient fasting and at 30 minutes and 2 hours after the ingestion of 15 mg of calcium in orange juice. Single photon absorptiometry was used to measure bone mineral density of the middle and distal radius. The mean fasting plasma levels of iCT for patients undergoing subtotal thyroidectomy was 27 +/- 2 mumol/L; women treated with radioactive iodine, 26 +/- 2; women undergoing subtotal thyroidectomy followed by radioactive iodine, 24 +/- 2, and for normal control women, 48.5 +/- 4.7. The mean stimulated iCT level of each of the patient groups was significantly lower than that of the normal controls (p = 0.01). There were no significant differences among the groups. Although there was an increased loss of bone mineral density in postmenopausal patients, with age and race as covariates, the bone densities of the distal radius in women undergoing subtotal thyroidectomy and/or receiving radioactive iodine were not significantly lower than those of normal control subjects (p greater than 0.05). These findings are consistent with other observations that patients treated by thyroidectomy and/or radioactive iodine for Graves' disease have lower basal levels of calcitonin and decreased calcitonin response to a provocative stimulus. Whether this loss of calcitonin reserve is a significant factor in development of postmenopausal osteoporosis remains unanswered.

Adult↗
PubMed1977

The distribution of radioactivity in pregnant rats after repeated oral doses of the diuretic agent Etozolin.

1. The distribution of radioactivity has been studied by whole-body autoradiography after administration of daily oral doses of (2-14C)-ethyl (Z)-(3-methyl-4-oxo-5-piperidino-thiazolidin-2-ylidene)acetate (etozolin, Gö 687, Elkapin) at a dose level of 100mg/kg to pregnant rats during the 10th to the 17th day of gestation. 2. After the last dose, most of the radioactivity was excreted rapidly and was mainly assoicated with the gastrointestinal and urinary tracts and kidneys of the mothers. 3. Maximal distribution in the mothers occurred at 3--6 h after the last dose, and radioactivity at these times was detectable also in the lungs, muscle mass, fat, mammary and uterine tissue, the reticuloendothelial system, placentae, some ducted and endocrine glands, and in blood, but not in brain or spinal cord. At 4 days, traces of radioactivity had persisted in kidneys, liver, lungs, thyroid and placentae. 4. Radioactivity was present in low and uniform concentrations in most foetal tissues such as the heart, lungs and lens and in even lower concentrations in the brains of the foetuses during 3--6 h after dosing, but was not detected in foetal tissues at 2 days. Concentrations of radioactivity in maternal tissues were at all times much higher compared with those in foetal tissues at corresponding times after dosing.

Administration, Oral↗
PubMed1983

Accumulation of radioactively labeled antithyroglobulin antibody by thyroid carcinoma.

The present experiments were undertaken to investigate (1) accumulation of radioactively labeled anti-thyroglobulin antibody by thyroid carcinomas and (2) the mechanism by which radioactively labeled antibody reaches to and stays in carcinoma cells. Anti-thyroglobulin antibody was purified by affinity chromatography using serum obtained from a patient with Hashimoto's disease. 125I-labeled anti-thyroglobulin antibody was injected into nude mice bearing transplanted human thyroid carcinomas. Scintigrams were taken 3 and 7 days after injection. Mice were killed thereafter and the radioactivity in each tissue and in serum was analyzed by gel filtration and affinity column chromatography of thyroglobulin, anti-thyroglobulin antibody and anti-human IgG antibody. In a total thyroidectomized patient with a metastatic thyroid carcinoma of the lymph node, 131I-labeled antibody was injected and scintigraphy and blood sampling performed for 7 days after injection. Scintigrams of the mice clearly showed the highest density over the transplanted carcinoma. Most radioactivity in the carcinoma was found to be in the thyroglobulin-antibody immune complex, while in other tissues, including serum samples, the radioactively was in free anti-thyroglobulin antibody. Scintigrams of the patient also showed a hot area over a metastatic carcinoma of the lymph node. It is concluded that (1) radioactively labeled anti-thyroglobulin antibody is accumulated by thyroid carcinoma in spite of the presence of thyroglobulin in blood and stays in cells as thyroglobulin-antibody immune complex, and (2) radioimmunodetection of thyroid carcinomas using labeled anti-thyroglobulin antibody is useful especially for patients with metastases which produces thyroglobulin and do not take up radioiodide.

Animals↗
PubMed1976

USAN assigned to radioactive pharmaceutical.

The United States Adopted Names (USAN) applicable to radioactive pharmaceuticals are composed of the names of the basic compound serving as the carrier for the radioactivity, the symbol for the radioactive isotope, and the atomic weight (since several radioactive isotopes of a given element may be in use--see listing under iodine). The following listing of nonproprietary names (shown in boldface type) is arranged in alphabetical order according to the English name of the radioactive element. The isotopes of hydrogen are listed under their specific names, deuterium and tritium. Radioactive pharmaceuticals are often supplied by the manufacturers under a designation equivalent to the adopted nonproprietary name and are listed as such; specific trademarks are given in brackets when they exist. Basic information relative to these lists was given in the editorial that accompanied the first such listing.

Pharmaceutical Preparations↗
PubMed1997

Advantages and limitations of radioactive stents.

The concept of radioactive stents was initiated to prevent restenosis after angioplasty in patients with coronary artery disease. We review the modes of fabrication, dosimetry and the biological effects of radioactive stents. Radioactive stents deliver ionizing radiation continuously at very low-dose rates according to the half-life of the incorporated radioisotopes. The activity levels of radioactive stents are up to 10,000 times lower than activity levels of sources used for catheter-based vascular brachytherapy. Radioactive stents allow uniform dose distribution and precise dosimetry because of the direct source contact with the circumference of the vessel. Animal studies show that these stents can potently inhibit smooth muscle cell proliferation and neointimal hyperplasia. A persistent inhibition of neointimal hyperplasia appears to be dose dependent. Local or systemic side effects related to the irradiation were not observed. A limitation of radioactive stents could be the dose-dependent delay in stent endothelialization which, however, did not cause thrombotic vessel occlusion in animal experiments. Whether a delay in stent endothelialization is associated with an increased rate of occlusive stent thrombosis in humans requires further studies.

Animals↗
PubMed1998

[Investigation on feasibility of using a gamma camera for the measurement of blood radioactivity].

The present study was undertaken to determine whether gamma cameras can be used to measure radioactivity in samples, e.g. in blood. Aqueous 123I solution with a concentration of 10.3 MBq/ml was infused at a volume of one ml into a blood-sampling vial having an internal diameter of 22.5 mm. Various concentrations of radioactivity were generated by leaving the vial and taking radioactive decay into account. Static images were acquired for five minutes with a gamma camera using a 64 x 64 matrix to measure radioactivity counts, and the regions of interest with 7 x 7 pixels (21 mm x 21 mm) were defined on the image. The results showed that there was a good linear correlation between the radioactivity counts measured with the gamma camera without collimator and those measured with the well-type scintillation counter in the range between 0.032 kBq/ml and 279 kBq/ml. It therefore appears that gamma cameras can be substituted for well-type scintillation counters in the measurement of radioactivities in samples.

Blood↗
PubMed1998

Strategies to reduce renal radioactivity levels of antibody fragments.

Antibody fragments such as Fab and single-chain Fv fragments possess many advantages over intact antibodies as vehicles to deliver radioactivity for diagnostic and therapeutic applications. However, radiolabled antibody fragments exhibited high and persistent localization of the radioactivity in the kidney, which compromises diagnostic accuracy and therapeutic effectiveness. Recent studies indicated that the persistent localization of renal radioactivity would be originated from the re-absorption of glomerularly-filtered radiolabeled antibody fragments, followed by the retention of the radiometabolites generated after degradation in the lysosomal compartment of the renal cells. Two major approaches have been performed to reduce the renal radioactivity levels of antibody fragments. One is to block the reabsorption of radiolabeled antibody fragments themselves at the proximal tubular cells from the luminal fluid by administration of basic amino acids such as L-lysine. The other approach is to decrease the residence time of the radiometabolites within the lysosomal compartments of the renal cells by introducing a cleavable linkage between antibody fragments and radiometabolites of rapid urinary excretion. Another approach to reduce renal radioactivity levels of antibody fragments may be to release radiolabeled compound of urinary excretion from glomerularly-filtered antibody fragments before they are reabsorbed into the renal cells by the action of brush border enzymes present on the lumen of the renal proximal cells. In this paper, recent studies of the three approaches to reduce the renal radioactivity levels of antibody fragments are briefly reviewed.

Antibodies, Monoclonal↗
PubMed2003

Radioactive contamination of bottom sediments in the upper reaches of the Techa river: analysis of the data obtained in 1950 and 1951.

A stationary sorption model has been developed for re-evaluating and analysing archive data from 1950-1951 on the radioactive contamination of Techa river bottom sediments close to the site of liquid radioactive waste discharge. In general, good agreement was obtained between calculations and measurements, which substantiates further the assumptions and conclusions in two preceding articles, on the radionuclide composition of discharged liquid radioactive waste. Estimates on the effective liquid radioactive waste discharges given here are significantly different from those deduced in the 1950s, i.e. in summer 1950 and October 1951. The results are discussed in relation to the Techa River Dosimetry System 2000 (TRDS-2000) that has recently been presented to serve as a means for estimating doses to the Techa river residents. Parameter values describing the exponential decrease of bottom sediment contamination along the river due to short-lived radionuclides, such as (106)Ru, and (144)Ce, agree reasonably with those used in TRDS-2000. However, for other radionuclides, such as (95)Zr, (95)Nb, (91)Y, (90)Sr and (137)Cs, substantial differences are found. It is demonstrated that water flow rate, width of the river, and surface area of bottom sediments are important parameters which were not adequately taken into account in TRDS-2000. Also, the stirring-up of contaminated bottom sediments and their subsequent transport by the water flow are seen to be an important mechanism that governs the radionuclide transport downstream. This mechanism was not included in the TRDS-2000 model. It is concluded that the sorption model used in TRDS-2000 for the reconstruction of radioactive contamination of water and bottom sediments of the Techa river in 1949-1951, is subject to considerable errors. While the present paper is focussed on details of the dosimetric modelling, the implications for the Techa river dosimetry are major. They will be further elucidated in a forthcoming paper.

Adsorption↗
PubMed2002

Determination of degradation of radioactivity and its kinetics in aerobic composting.

In this study, the kinetics of disappearance of radioactivity in aerobic composting was investigated. For this purpose, compost materials were prepared by mixing sugar beet wastes, wine factory wastes (grape wastes), straw and biological treatment sludge in different amounts. While alpha-radioactivity was not initially detected in all composting materials, the composting materials had some beta-radioactivity. In the mixtures of sugar beet wastes--straw-biological treatment sludge (1), sugar beet wastes-wine factory wastes (grape wastes)-biological treatment sludge (II) and wine factory wastes (grape wastes)-biological treatment sludge (III), the beta-radioactivity reduced by 82%, 58%, 85% respectively of initial values after 52 d. The beta-radioactivity degradation in the composting process could be represented by first-order kinetics and reaction rate constants of mixtures of I, II and III were k = 0.0693 d(-1) (R2 - 0.84), k = 0.0453 d(-1) (R2 = 0.98), k = 0.0234 d(-1) (R2 = 0.97), respectively.

Beta vulgaris↗
PubMed2002

Influence of dust loading on the alpha-particle energy resolution of continuous air monitors for thin deposits of radioactive aerosols.

Alpha-particle continuous air monitors must sometimes be operated in dusty environments where significant dust loading of the filter can be anticipated. It is important to understand how this dust loading affects the response of the continuous air monitors. Not only must a filter be changed if there is a reduction in airflow, but a change may be necessary if the energy resolution deteriorates and the continuous air monitor loses sensitivity and specificity for the radioactive aerosols of interest. A series of experiments were conducted to investigate alpha-particle energy resolution of continuous air monitor filters, particularly under dust loading conditions. Aerosol particles of various sizes were tagged with radon decay products to serve as surrogates for radioactive aerosols of interest such as plutonium or uranium. While the size of radioactive aerosols, filter type, and dust type affected the energy resolution, the thickness of an underlying (nonradioactive) dust layer did not show significant effect for the materials studied and a loading range of 0.01-10 mg x cm(-2). Our results indicate that it is possible for continuous air monitors to detect the release of radioactive aerosols with little deterioration in energy resolution under conditions of significant dust loading provided that the deposited layer of radioactive aerosols remains thin (< or = 0.1 mg x cm(-2)).

Aerosols↗
PubMed1975

[A proposal to improve radioactive waste disposal following metabolic radio-iodine therapy].

After metabolic radio-iodine treatments of carcinomas of the thyroid, increased activities of I 131 are secreted from the patient's body by the renal route. The highly radioactive urine represents a serious danger of contamination for the nursing staff and third persons. The ideal conditions for the isolation of treated patients in a department disposing of a sewage disposal system of its own are not fulfilled at our hospital. Collection of radioactive urine of the patients for the purpose of annihilating radioactivity over several half-lifes of I 131 is extremely intricate. For this reason, we developed a filter system by means of which we were able to free the radioactive urine of the first five female patients treated from more than 99% of radioactivity. The contaminated locked filter patterns can be stored as "closed radio-sources" essentially more securely and space saving. The advantages of this system and their practical possibilities of use are discussed.

Female↗