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PubMed1991

Studies of radioactivity produced by the Hiroshima atomic bomb: 1. Neutron-induced radioactivity measurements for dose evaluation.

This review summarizes measurements made of 152Eu and 60Co radioactivity induced by neutron radiation from the Hiroshima atomic bomb (A-bomb) with the goal of estimating the neutron dose released by the bomb. Prior to these measurements, A-bomb-irradiated specimens such as rocks and pieces of concrete, which had not been shielded were collected. The specific radioactivity obtained (in bequerels per gram of Eu or Co) were compared with those calculated from DS86 neutrons. Findings of usefulness of 152Eu data within 700 m ground range are reported and systematic differences between measured activities and calculations are discussed. The 152Eu data were also useful for the discussion of circular asymmetry, and there was no asymmetry within the experimental errors. This review also covers the similar difference found in 32P data, which were measured immediately after the A-bomb, along with the other 152Eu and 60Co data. The need for more measurements of 152Eu activity in samples farther away from the hypocenter in order to verify the DS86 calculations is also discussed.

Humans↗
PubMed2003

Separation and recovery of radioactive and non-radioactive toxic trace elements from aqueous industrial effluents.

An update is presented on liquid membrane-based processes as viable and relevant alternatives to conventional approaches such as precipitation, solvent extraction, ion exchange processes and electrochemical techniques for the removal and recovery of some toxic and/or valuable trace metal ions including some actinides and fission products e.g. U, Am, Y etc and As, Cd, Co, Cr, Cu, Hg, Ni, Pb, Zn etc from radioactive as well as non-radioactive aqueous waste solutions respectively. In particular, results of experiments aimed at developing supported liquid membrane(SLM)-based process using commercially available porous membranes and indigenously prepared track--etch membranes (TEMs) have been critically examined in laboratory studies to generate basic data needed to evaluate their utility for continuous operation without regeneration. These include effect of pore size, porosity, optimum pore size and their reusability. It is clearly demonstrated that indigenously prepared 10 microm thick TEMs with a porosity in the range of 2-5% give comparable transport rates for metal ions-matching with that of commercial membranes of much higher thickness (160 microm) and higher porosity of 60-85%. The smaller thickness of TEMs more than compensates for their lower porosity. It is shown that because of their well defined pore characteristics TEMs could serve as model supports in SLM studies. By comparing the values of permeability coefficient (P) for TEM and polytetraflouroethylene (PTFE) supports for the transport of Pb2+ chosen as a typical divalent metal ion, and using di-2 ethyl hexyl phosphoric acid (D2EHPA) as the carrier, it is unambiguously proved that diffusion of the metal complex across the membrane is the rate controlling step in metal ion transport in SLM-based processes. An overview of the experimental findings along with future outlook and suggestions for further work are presented in this paper.

Actinoid Series Elements↗
PubMed1992

Sensitive mRNA detection using unfixed tissue: combined radioactive and non-radioactive in situ hybridization histochemistry.

In the present study some experimental parameters for in situ hybridization histochemistry (ISHH) have been analysed using 35S-labelled and alkaline phosphatase-conjugated probes, in order to develop a reproducible double-labelling procedure. We have compared the total exclusion of tissue fixation with tissue sections fixed by immersion in formalin. In addition, the effect of dithiothreitol was assessed both when combining radiolabelled and non-radioactive probes on a single tissue section and when the probes were used separately. Hybridization of unfixed tissue resulted in stronger specific labelling and lower background both for radiolabelled and alkaline phosphatase-conjugated probes. No loss in tissue preservation was seen at the light microscopic level after hybridization of unfixed tissue. High concentrations (200 mM) of dithiothreitol strongly suppressed background when using 35S-labelled probes, whereas in the non-radioactive procedure, alkaline phosphatase labelling could only be achieved with very low dithiothreitol concentrations (less than 1 mM). This incompatibility led to a protocol using unfixed tissue sections and a sequential hybridization procedure, with the radiolabelled probe and high concentrations of dithiothreitol in the first step and the alkaline phosphatase-conjugated probe without dithiothreitol in the second step.

Alkaline Phosphatase↗
PubMed2000

Accuracy considerations when using early (four- or six-hour) radioactive iodine uptake to predict twenty-four-hour values for radioactive iodine dosage in the treatment of Graves' disease.

Although literature has offered methods to predict 24-hour radioactive iodine uptake values from early (4- to 6-hour) measurements, the resultant dosage errors have not been examined. Potential errors include underdosage, overdosage, and a failure to recognize rapid turnover patients (early-to-late uptake ratios > or = 1) who are at high risk for treatment failure and full-body radiation exposure. We developed and tested a novel method for minimizing error involved in using a single early uptake measurement to derive late uptake. From a retrospective analysis of 203 Graves' disease patients, receiver operating characteristic (ROC) curve analysis enabled us to identify patients likely to experience rapid turnover and therefore should receive 24-hour studies. Twenty-four-hour uptake measurements are necessary with 77% or more 4-hour uptake values and 80% or more 6-hour values. After eliminating these patients, we developed linear regression equations to predict the 24-hour uptake from 4-hour (n = 61) and 6-hour (n = 22) rule groups, testing their efficacy on separate 4-hour (n = 61) and 6-hour (n = 21) patient groups. We also used our test population to measure error in four early-to-late uptake conversion formulas presented in the literature. Error involved in these predictions ranged from a 10.6% overestimate for 4-hour calculations to a 5.9% underestimate for 6-hour calculations. When applied to two dosage formulas incorporating gland size, absorbed dose, and 24-hour uptake, average dosage error was 7%. In comparison to the other sources of error radioactive iodine (131I) dosimetry, potential error in predicting 24-hour uptake from 4- or 6-hour uptake values is low.

Graves Disease↗
PubMed2004

Resrad-recycle: a computer model for analyzing radiation exposures resulting from recycling radioactively contaminated scrap metals or reusing radioactively surface-contaminated materials and equipment.

RESRAD-RECYCLE is a computer code designed by Argonne National Laboratory (ANL) to be used in making decisions about the disposition of radioactively contaminated materials and scrap metals. It implements a pathway analysis methodology to evaluate potential radiation exposures resulting from the recycling of contaminated scrap metals and the reuse of surface-contaminated materials and equipment. For modeling purposes, it divides the entire metal recycling process into six steps: (1) scrap delivery, (2) scrap melting, (3) ingot delivery, (4) product fabrication, (5) product distribution, and (6) use of finished product. RESRAD-RECYCLE considers the reuse of surface-contaminated materials in their original forms. It contains representative exposure scenarios for each recycling step and the reuse process; users can also specify scenarios if desired. The model calculates individual and collective population doses for workers involved in the recycling process and for the public using the finished products. The results are then used to derive clearance levels for the contaminated materials on the basis of input dose restrictions. The model accounts for radiological decay and ingrowth, dilution and partitioning during melting, and distribution of refined metal in the various finished products, as well as the varying densities and geometries of the radiation sources during the recycling process. A complete material balance in terms of mass and radioactivity during the recycling process can also be implemented. In an international validation study, the radiation doses calculated by RESRAD-RECYCLE were shown to agree fairly well with actual measurement data.

Body Burden↗
PubMed1989

Detection of mRNA molecules coding for neuropeptide hormones of the pond snail Lymnaea stagnalis by radioactive and non-radioactive in situ hybridization: a model study for mRNA detection.

To develop and optimize non-radioactive in situ hybridization techniques for mRNA detection, we used the neuropeptidergic system of the pond snail Lymnaea stagnalis as a biological model system. First, we investigated the in situ hybridization procedure using radioactive-labeled cDNA and synthetic oligonucleotide probes specific for egg-laying hormone (ELH) mRNA and molluscan insulin-like peptide (MIP) mRNA. The results show an intense grain deposit above the caudodorsal cells and light-green cells expressing, respectively, ELH mRNA and MIP mRNA. Good results with relation to signal strength and tissue morphology were obtained with freeze-dry paraformaldehyde vapor fixation. The necessity to perform tissue pre-treatment appeared to be dependent on the cell type of interest. The optimized in situ hybridization protocol proved to be applicable using probes that are either sulfonated/transaminated or labeled with acetylaminofluorene (AAF). In situ hybridization of such haptenized probes led to intense and specific staining of the cytoplasm of the caudodorsal cells. Egg-laying hormone mRNA appeared not to be homogeneously distributed in the cytoplasm but showed a "patch-like" pattern. Nuclear and axoplasmic staining for mRNA was also observed.

2-Acetylaminofluorene↗
PubMed1990

Detection of calcitonin-encoding mRNA by radioactive and non-radioactive in situ hybridization: improved colorimetric detection and cellular localization of mRNA in thyroid sections.

The localization of mRNA encoding calcitonin was studied by in situ hybridization using 35S-labeled RNA probes and biotin-labeled DNA probes. Radiolabeled probes were detected by autoradiography and biotin-labeled probes by streptavidin-biotin-peroxidase. To intensify the colorimetric signal, the indirect avidin-biotin complex (ABC) method was performed. However, the results were often variable. To improve the sensitivity, the peroxidase reaction signal was enhanced with a gold-silver deposit intensification reaction. To shorten the incubation times and to enhance the colorimetric reaction, several reaction steps were performed in a microwave oven. The localization of calcitonin mRNA in thyroid tissue, as detected with in situ hybridization, was confirmed by immunohistochemical localization of the calcitonin polypeptide. The results of in situ hybridization using biotinylated probes were compared to in situ hybridization using radioactive probes. Our data show that the results of in situ hybridization applied on frozen and paraffin-embedded sections using biotinylated DNA probes, detected with an indirect streptavidin-biotin-peroxidase reaction and intensified by silver-gold enhancement, were comparable to those obtained with radioactive probes. The localization of calcitonin encoding mRNA was in agreement with the localization of the calcitonin polypeptide.

Affinity Labels↗
PubMed1993

Combination of non-radioactive and radioactive in situ hybridization with immunohistochemistry: a new method allowing the simultaneous detection of two mRNAs and one antigen in the same brain tissue section.

We describe here a simple method for combining non-radioactive and radioactive in situ hybridization and immunohistochemistry on the same brain tissue section. This approach was first developed on the well-characterized hypothalamo-neurohypophyseal system, facilitating the optimization of the triple-labeling procedure and the verification of labeling specificity. We report the simultaneous detection of vasopressin (VP) mRNA with a digoxigenin-labeled oligonucleotide, oxytocin (OT) mRNA with a 35S-labeled oligonucleotide, and OT peptide in the same 12-microns cryostat section. This was performed on floating sections as follows: first, the two probes were hybridized simultaneously; second, the peptide was detected with an immunoperoxidase-DAB procedure; third, the digoxigenin-labeled probe was detected with an alkaline phosphatase-NBT/BCIP technique; and finally, the 35S-labeled probe was detected by histological autoradiography. We also demonstrate that this approach is suitable for the simultaneous detection of tyrosine hydroxylase and two less abundant mRNAs, vasoactive intestinal peptide and vasopressin mRNAs, in the suprachiasmatic nucleus. The combination of the three techniques did not significantly diminish their specificity or sensitivity. In conclusion, this new method, permitting the simultaneous detection of three different products of gene expression in the same section, could be useful for further analysis of the phenotypic organization and its plasticity in endocrine or neural tissues.

Animals↗
PubMed1993

[Value of radioactive cesium content in selected food products. I. Content of radioactive cesium in dried milk (1987-1988)].

The content of radioactive cesium in dried and dried skimmed milk from selected dairies was double determined. The highest content was found in samples from milk from OSM Siedlce (98 Bq/kg) and skimmed milk from Radzyń Podlaski and Ostrołeka, (the former 90, the latter 62 Bq/kg). The lowest level of radioactive caesium was observed in samples from dried milk from Sieradz, Słupsk, Września, Olecko and Elblag (about or below 10 Bq/kg). Although those levels of contamination with radiocesium didn't exceed values recommended by FAO they were determined as high for year 1987/88 as compared milk data from previous 1985 year.

Animals↗
PubMed1995

Determination of amplification level of the c-erbB-2 proto-oncogene in human breast carcinomas: a comparative study between non-radioactive and radioactive labelling.

A quantitative method of polymerase chain reaction (PCR) using both digoxigenin and radioactive labelled probes has been used for the detection of the c-erbB-2 proto-oncogene amplification in breast carcinomas with formalin-fixed paraffin-embedded tissue sections. c-erbB-2 proto-oncogene amplification has been demonstrated in 14 infiltrating ductal carcinomas. The technique consisted of the co-amplification of c-erbB-2 and IFN-gamma (interferon-gamma) genes. The latter was considered as a single copy gene per genome-equivalent. The aim of this study was to compare two quantitative PCR techniques based on the incorporation of either digoxigenin-11-dUTP or 32P-dCTP, during amplification. For the colorigenic method, using the Dig system, after electrophoresis and transfer, the specific bands were revealed with a chromogenic substrate of phosphatase. Their intensity estimated by scanning photometry following blot transparisation. After electrophoresis, the radioactive gel was submitted to radioautography and the band intensities evaluated by scanning spectrophotometry. For the 14 samples, a good agreement between both methods was noted. The colorigenic method is a valuable alternative to radiolabelling due to: i) time saving, ii) reagent conservation, iii) safe manipulation and iv) sensitivity of the same order for both methods.

Base Sequence↗
PubMed2002

Radioactive contamination in the marine environment adjacent to the outfall of the radioactive waste treatment plant at ATOMFLOT, northern Russia.

RTP "ATOMFLOT" is a civilian nuclear icebreaker base located on the Kola Bay of northwest Russia. The objectives of this study were to determine the distributions of man-made radionuclides in the marine environment adjacent to the base, to explain the form of the distributions in sediments and to derive information concerning the fate of radionuclides discharged from ATOMFLOT. Mean activity concentrations (d.w.) for surface sediment, of 63 Bq kg(-1 137Cs, 5.8 Bq kg(-1) 90Sr and 0.45 Bq kg(-1 239,240)Pu were measured. Filtered seawater activity levels were in the range of 3--6.9 Bq m(-3) 137Cs, 2.0-11.2 Bq m(-3) 90Sr, and 16-40 m Bq m(-3), 239,240Pu. Short-lived radionuclides were present at sediment depths in excess of 10cm indicating a high degree of sediment mixing. Correlations of radionuclide activity concentrations with grain-size appear to be absent; instead, the presence of relatively contaminated sediment appears to be related to the existence of radioactive particles.

Environmental Monitoring↗
PubMed1991

Studies of radioactivity produced by the Hiroshima atomic bomb: 2. Measurements of fallout radioactivity.

Three studies of fallout measurements were reviewed for the discussion of possible radioactivity intake from the Hiroshima atomic bomb. The first study discussed correlations between enriched 234U and 137Cs specific activities from the measurement of soil samples collected in the "black rain" area. The second study measured 137Cs activity on the rock and roof tile samples collected in the hypocenter area immediately after the explosion. Some of the rock and roof tile samples collected near the hypocenter had a small but detectable amount of 137Cs activity. However, it has been determined that 137Cs exposure, for example, was negligible compared with DS86 dose estimates, since these activity levels were low. The third study detected 90Sr activity in some of the specimens of human bones exhumed on Ninoshima Island. This study compared the difference in activity between the bone head and shaft, with higher activities obtained in the bone head. This fact suggests a short intake period for this activity, however, the levels of 90Sr contamination were too low to allow a discussion of the exposure risks.

Humans↗
PubMed1991

A review of forty-five years study of Hiroshima and Nagasaki atomic bomb survivors. Residual radioactivity in neutron-exposed objects and residual alpha radioactivity in black rain areas.

The residual Eu-142 radioactivity due to the atomic bomb explosion in 1945 was first found in 1976 by in-situ high resolution gamma-ray spectrometry at Hiroshima. Since then, various studies on this nuclide have continued not only in Hiroshima but also in Nagasaki and they have contributed to the reevaluation of the neutron dose due to the A-bombing. By radiochemical separation methods and alpha-ray spectrometry, rather high levels of plutonium were found in the surface soil and in the bottom sediment of water reservoir which were collected at "Black rain area" in Nagasaki. The U-234/U-238 activity ratios for the uranium leached with 0.1 HNO3 from the surface of soil samples were found to be relatively higher for the samples which were collected at "Black rain area" in Hiroshima.

Alpha Particles↗
PubMed1997

A non-radioactive and two radioactive assays for selenophosphate synthetase activity.

Selenophosphate synthetase catalyzes the formation of monoselenophosphate (SePO3(3-)) from ATP and selenide (reaction 1). [formula: see text] In one assay frequently used, [8-14C]AMP formation from [8-14C]ATP is estimated after separation of the nucleotides by thinlayer chromatography. An alternative non-radioactive assay in which the AMP product is estimated using AMP deaminase is described. The highly oxygen-labile selenophosphate product can be estimated in an assay employing [gamma-32P]ATP. The 32P-labeled selenophosphate is converted to [32P]orthophosphate by treatment with iodine and estimated after removal of residual [32P]ATP on charcoal.

Adenosine Monophosphate↗
PubMed1975

Radioactive antigen suicide of an anti-DNP (2,4-dinitrophenyl) clone. II. Follow-up of clones relatively resistant to radioactive antigen suicide when initially selected.

After suicide of the anti-dinitrophenyl (DNP) clone E21 in a previous experiment (Eur. J. Immunol. 1975. 5:58) several new clones (S clones) appeared promptly in the recipients. There was compelling evidence that they were then resistant to suicide, relative to E21. We now report further studies on these S clones and their antibodies. The antibodies of half of the S clones had affinities ten to one hundred times higher than E21 (3 x 10(-7) M); none was lower. The four tested were also able to bind DNP on the particular conjugate used for the suicide procedure. Three of the S clones were serially propagated, they showed a very great capacity for proliferation, transferring into 510, 85 and 110 recipients each. When their cells were tested at subsequent passages, they recovered early after inhibition by radioactive antigen. Two S clones may still have been somewhat refractory to suicide but, probably in all three, rapid proliferation was largely responsible for the recovery of the few cells escaping suicide, and helped them to appear suicide resistant.

Age Factors↗
PubMed1995

Treatment with propylthiouracil before radioactive iodine therapy is associated with a higher treatment failure rate than therapy with radioactive iodine alone in Graves' disease.

Older reports have suggested that the use of antithyroid drugs with radioactive iodine-131 (RAI) results in higher rates of persistent hyperthyroidism than treatment with RAI alone. Our objective was to determine if propylthiouracil (PTU) given prior to RAI would be associated with a higher single dose RAI failure rate than treatment with RAI alone. Patients were considered treatment failures if a second dose of RAI was required to produce euthyroidism or hypothyroidism. All study patients stopped PTU at least 4 days before RAI therapy and did not receive PTU after RAI. The overall failure rate of one course of treatment in the 86 study patients was 17% (15/86). Persistent hyperthyroidism was seen in 4% of patients (2/48) treated with only RAI and in 34% of patients (13/38) receiving RAI after pretreatment with PTU (p = 0.003). Patients were treated with PTU for a mean of 151 +/- 32 days. There were no significant differences in race, gender, thyroid size, RAI dose, or days of follow-up between patients receiving RAI alone and those receiving PTU before RAI therapy. These data suggest that pretreatment with PTU leads to a higher failure rate even if PTU is discontinued at least 4 days before RAI therapy and not restarted after RAI dosing. Consideration should be given to increasing the dose of RAI in patients pretreated with PTU to ensure adequate treatment of Graves' disease.

Adult↗