Sample records for 90nb 93mmo 96tc

  1. High-spin states in the {sup 96}Tc nucleus

    Energy Technology Data Exchange (ETDEWEB)

    Bucurescu, D.; Cata-Danil, G.; Cata-Danil, I.; Ivascu, M.; Marginean, N.; Rusu, C.; Stroe, L.; Ur, C.A. [National Inst. of Physics and Nuclear Engineering, Bucharest (Romania); Gizon, A.; Gizon, J. [Inst. des Sciences Nucleaires, IN2P3-CNRS/UPJ, Grenoble (France); Nyako, B.; Timar, J.; Zolnai, L. [Inst. of Nuclear Research, Debrecen (Hungary); Boston, A.J.; Joss, D.T.; Paul, E.S.; Semple, A.T. [Oliver Lodge Lab., Liverpool Univ. (United Kingdom); Parry, C.M. [Dept. of Physics, York Univ., Heslington, York (United Kingdom)


    High-spin states in the {sup 96}Tc nucleus have been studied with the reactions {sup 82}Se({sup 19}F,5n{gamma}) at 68 MeV and Zn({sup 36}S,{alpha}pxn) at 130 MeV. Two {gamma}-ray cascades (irregular bandlike structures) have been observed up to an excitation energy of about 10 MeV and spin 21-22{Dirac_h}. (orig.)

  2. Projected shell model study of band structure of 90Nb (United States)

    Kumar, Amit; Singh, Dhanvir; Gupta, Anuradha; Singh, Suram; Bharti, Arun


    A systematic study of two-quasiparticle bands of the odd-odd 90Nb nucleus is performed using the projected shell model approach. Yrast band with some other bands have been obtained and back-bending in moment of inertia has also been calculated and compared with the available experimental. On comparing the available experimental data, it is found that the treatment with PSM provides a satisfactory explanation of the available data.

  3. {sup 90}Nb - a potential PET nuclide. Production and labeling of monoclonal antibodies

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    Radchenko, V.; Roesch, F. [Mainz Univ. (Germany). Inst. of Nuclear Chemistry; Hauser, H.; Eisenhut, M. [German Cancer Research Center, Heidelberg (Germany). Radiopharmaceutical Chemistry; Vugts, D.J.; Dongen, G.A.M.S. van [VU University Medical Center, Amsterdam (Netherlands). Dept. of Nuclear Medicine and PET Research; VU University Medical Center, Amsterdam (Netherlands). Dept. of Otolaryngology/Head and Neck Surgery


    Fast progressing immuno-PET gives reasons to develop new potential medium-long and long-lived radioisotopes. One of the promising candidates is {sup 90}Nb. It has a half-life of 14.6 h, which allows visualizing and quantifying processes with medium and slow kinetics, such as tumor accumulation of antibodies and antibodies fragments or polymers and other nanoparticles. {sup 90}Nb exhibits a high positron branching of 53% and an optimal energy of {beta}{sup +} emission of E{sub mean} = 0.35 MeV only. Consequently, efficient radionuclide production routes and Nb{sup V} labeling techniques are required. {sup 90}Nb was produced by the {sup 90}Zr(p,n){sup 90}Nb nuclear reaction on natural zirconium targets. No-carrier-added (n.c.a.) {sup 90}Nb was separated from the zirconium target via a multi-step separation procedure including extraction steps and ion-exchange chromatography. Protein labeling was exemplified using the bifunctional chelator desferrioxamine attached to the monoclonal antibody rituximab. Desferrioxamine was coupled to rituximab via two different routes, by the use of N-succinyl-desferrioxamine (N-suc-Df) and by means of the bifunctional derivative p-isothiocyanatobenzyl-desferrioxamine B (Df-Bz-NCS), respectively. Following antibody modification, labeling with {sup 90}Nb was performed in HEPES buffer at pH 7 at room temperature. In vitro stability of the radiolabeled conjugates was tested in saline buffer at room temperature and in fetal calf serum (FCS) at 37 C. The selected production route led to a high yield of 145 {+-} 10 MBq/{mu}A h of {sup 90}Nb with high radioisotopic purity of > 97%. This yield may allow for large scale production of about 10 GBq {sup 90}Nb. The separation procedure resulted in 76-81% yield. The Zr/{sup 90}Nb decontamination factor reaches 10{sup 7}. Subsequent radiolabeling of the two different conjugates with {sup 90}Nb gave high yields; after one hour incubation at room temperature, more than 90% of {sup 90}Nb-Df-mAb was

  4. Separation of {sup 90}Nb from zirconium target for application in immuno-PET

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    Radchenko, V.; Roesch, F. [Mainz Univ. (Germany). Inst. of Nuclear Chemistry; Filosofov, D.V.; Bochko, O.K.; Lebedev, N.A.; Rakhimov, A.V. [Joint Institute for Nuclear Research, Dubna, Moscow Region (Russian Federation). Dzhelepov Laboratory of Nuclear Problems; Hauser, H.; Eisenhut, M. [German Cancer Research Center, Heidelberg (Germany). Radiopharmaceutical Chemistry; Aksenov, N.V.; Bozhikov, G.A. [Joint Institute for Nuclear Research, Dubna, Moscow Region (Russian Federation). Flerov Laboratory of Nuclear Reactions; Ponsard, B. [Belgian Nuclear Research Centre (SCKCEN), Mol (Belgium). Radioisotopes and NTD Silicon Production


    Fast progressing immuno-PET asks to explore new radionuclides. One of the promising candidates is {sup 90}Nb. It has a half-life of 14.6 h that allows visualizing and quantifying biological processes with medium and slow kinetics, such as tumor accumulation of antibodies and antibodies fragments or drug delivery systems and nanoparticles. {sup 90}Nb exhibits a positron branching of 53% and an average kinetic energy of emitted positrons of E{sub mean} = 0.35 MeV. Currently, radionuclide production routes and NbV labeling techniques are explored to turn this radionuclide into a useful imaging probe. However, efficient separation of {sup 90}Nb from irradiated targets remains in challenge. Ion exchange based separation of {sup 90}Nb from zirconium targets was investigated in systems AG 1 x 8 - HCl/H{sub 2}O{sub 2} and UTEVA-HCl. {sup 95}Nb (t{sub 1/2} = 35.0 d), {sup 95}Zr (t{sub 1/2} = 64.0 d) and {sup 92m}Nb (t{sub 1/2} = 10.15 d) were chosen for studies on distribution coefficients. Separation after AG 1 x 8 anion exchange yields 99% of {sup 90/95}Nb. Subsequent use of a solid-phase extraction step on UTEVA resin further decontaminates {sup 90/95}Nb from traces of zirconium with yields 95% of {sup 90/95}Nb. A semi-automated separation takes one hour to obtain an overall recovery of {sup 90/95}Nb of 90%. The amount of Zr was reduced by factor of 10{sup 8}. The selected separation provides rapid preparation (< 1 h) of high purity {sup 90}Nb appropriate for the synthesis of {sup 90}Nb-radiopharmaceuticals, relevant for purposes of immuno-PET. Applying the radioniobium obtained, {sup 90/95}Nb-labeling of a monoclonal antibody (rituximab) modified with desferrioxamine achieved labeling yields of > 90% after 1 h incubation at room temperature. (orig.)

  5. Nuclear data for the cyclotron production of 117Sb and 90Nb

    Institute of Scientific and Technical Information of China (English)

    Enferadi Milad; Sadeghi Mahdi


    This presented study is to make comparison of cross sections to produce 117Sb and 90Nb via different reactions with particle incident energy up to 70 MeV as a part of systematic studies on particle-induced activations on enriched Sn, Y2O3 and ZrO2 targets, theoretical calculation of production yield, calculation of required thickness of target and suggestion of optimum reaction to produce Antimony-117 and Niobium-90.

  6. Direct flow separation strategy, to isolate no-carrier-added {sup 90}Nb from irradiated Mo or Zr targets

    Energy Technology Data Exchange (ETDEWEB)

    Radchenko, Valery; Roesch, Frank [Mainz Univ. (Germany). Inst. of Nuclear Chemistry; Filosofov, Dmitry V.; Dadakhanov, Jakhongir [Joint Institute of Nuclear Research, Dubna (Russian Federation). Dzhelepov Laboratory of Nuclear Problems; Karaivanov, Dimitar V. [Joint Institute of Nuclear Research, Dubna (Russian Federation). Dzhelepov Laboratory of Nuclear Problems; Bulgarian Academy of Sciences, Sofia (Bulgaria). Inst. for Nuclear Research and Nuclear Energy; Marinova, Atanaska [Joint Institute of Nuclear Research, Dubna (Russian Federation). Dzhelepov Laboratory of Nuclear Problems; Sofia Univ. (Bulgaria). Faculty of Chemistry and Pharmacy; Baimukhanova, Ayagoz [Joint Institute of Nuclear Research, Dubna (Russian Federation). Dzhelepov Laboratory of Nuclear Problems; Institute of Nuclear Physics of the Republic of Kazakhstan, Almaty (Kazakhstan)


    {sup 90}Nb has an intermediate half-life of 14.6 h, a high positron branching of 53% and optimal β{sup +} emission energy of only E{sub mean} 0.35 MeV per decay. These favorable characteristics suggest it may be a potential candidate for application in immuno-PET. Our recent aim was to conduct studies on distribution coefficients for Zr{sup IV} and Nb{sup V} in mixtures of HCl/H{sub 2}O{sub 2} and HCl/oxalic acid for anion exchange resin (AG 1 x 8) and UTEVA resin to develop a ''direct flow'' separation strategy for {sup 90}Nb. The direct flow concept refers to a separation accomplished using a single eluent on multiple columns, effectively streamlining the separation process and increasing the time efficiency. Finally, we also demonstrated that this separation strategy is applicable to the production of the positron emitter {sup 90}Nb via the irradiation of molybdenum targets and isolation of {sup 90}Nb from the irradiated molybdenum target.

  7. {sup 90}Nb: potential radionuclide for application in immuno-PET. Development of appropriate production strategy and first in vivo evaluation of {sup 90}Nb-labeled monoclonal antibody

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    Radchenko, Valery


    Nuclear medicine is a modern and highly effective tool for the detection and treatment of oncological disease. Molecular imaging based on radiotracers includes single photon emission tomography (SPECT) and positron emission tomography (PET), which provide non-invasive tumor visualization on nano- and picomolar level, respectively. Currently, many novel tracers for more precise discovery of small tumors and metastases have been introduced and are under investigation. Many of them are protein-based biomolecules which nature herself produces as antigens for the eradication of tumor cells. Antibodies and antibody fragments play an important role in tumor diagnostics and treatment. PET imaging with antibodies and antibody fragments is called immuno-PET. The main issue that needs to be addressed is that appropriate radiotracers with half-lives related to the half-lives of biomolecules are needed. The development of novel radiotracers is a multistep, complicated task. This task includes the evaluation of production, separation and labeling strategy for chosen radionuclide. Finally, the biomolecule-radionuclide complex should be stable in time. An equally important factor is the economic suitability of the production strategy, which will lead to a key decision for future application of the developed radionuclide. In recent work, {sup 90}Nb has been proposed as a potential candidate for application in immuno-PET. Its half-life of 14.6 hours is suitable for application with antibody fragments and some intact antibodies. {sup 90}Nb has a relatively high positron branching of 53% and an optimal energy of β{sup +} emission of 0.35 MeV that can provide high quality of imaging with low dose of used radionuclide. First proof-of-principle studies have shown that {sup 90}Nb: (i) can be produced in sufficient amount and purity by proton bombardment of natural zirconium target (ii) can be isolated from target material with appropriate radiochemical purity (iii) may be used for

  8. Desferrioxamine as an appropriate chelator for 90Nb: comparison of its complexation properties for M-Df-Octreotide (M = Nb, Fe, Ga, Zr). (United States)

    Radchenko, Valery; Busse, Stefan; Roesch, Frank


    The niobium-90 radioisotope ((90)Nb) holds considerable promise for use in immuno-PET, due to its decay parameters (t½ = 14.6h, positron yield=53%, Eß(+)(mean) = 0.35 MeV and Eß(+)(max) = 1.5 MeV). In particular, (90)Nb appears well suited to detect in vivo the pharmacokinetics of large targeting vectors (50-150 kDa). In order to be useful for immuno-PET chelators are required to both stabilize the radionuclide in terms of coordination chemistry and to facilitate the covalent attachment to the targeting vector. Different chelators were evaluated for this purpose in terms of radiolabelling efficiency and stability of the radiolabelled Nb(V) complex and in order to determine the most suitable candidate for conjugation to a biologically relevant targeting vector. For the purpose of studying the complexation properties the niobium radioisotope (95)Nb was used as an analogue of (90)Nb, by virtue of its longer half-life (35 days) and lower cost (reactor-based production). Acyclic and cyclic chelators were investigated, with desferroxamine [Df: (N'-{5-[acetyl(hydroxy)amino]pentyl}-N-[5-({4-[(5-aminopentyl) (hydroxy)amino]-4-oxobutanoyl} amino)pentyl]-N-hydroxysuccinamide)] emerging as the best candidate. Greater than 99% radiolabelling was achieved at room temperature over a wide pH range. The (95)Nb-Df complex is sufficiently stable for immuno-PET (kinetics of the unconjugated chelator (Df) were retained for Df-succinyl-(D)Phe(1)-octreotide (Df-OC), with>90% labelling after 1h at room temperature over the pH range 5-7. Stability studies, performed in vitro in serum at physiological temperature (37 °C), revealed that 87 ± 2% of the radiolabelled molecule remained intact after 7 days. Competition studies with relevant metal ions (zirconium((IV)), gallium((III)) and iron((III))) have been performed with Df-OC to gain insight to the relative stability [Nb-Df]-OC complex to transmetallation. At equimolar metal ion concentrations the [Nb-Df]-OC complex showed the greatest

  9. Equilibrium and pre-equilibrium calculations of cross-sections of (, ) reactions on 89Y, 90Zr and 94Mo targets used for the production of 89Zr, 90Nb and 94Tc positron-emitting radionuclides

    Indian Academy of Sciences (India)

    R Baldik; H Aytekin; E Tel


    In this study, the pre-equilibrium and equilibrium calculations of cross-sections of 89Y(, ), 90Zr$(p, xn)$ and 94Mo(, ) reactions, which were used for the production of 89Zr, 90Nb and 94Tc positron-emitting radioisotopes, have been investigated. Pre-equilibrium calculations have been performed at different proton incident energies by using the hybrid, geometry-dependent-hybrid and full exciton models. The Weisskopf–Ewing model is used for calculating the equilibrium effects at the same incident energies. The calculated results have been discussed and compared with the experimental results.

  10. Nuclear data for the cyclotron production of ~(117)Sb and ~(90)Nb

    Institute of Scientific and Technical Information of China (English)

    Enferadi Milad; Sadeghi Mahdi


    This presented study is to make comparison of cross sections to produce 117Sb and 90Nb via different reactions with particle incident energy up to 70 MeV as a part of systematic studies on particle-induced activations on enriched Sn, Y2O3 and ZrO2 targets

  11. Labeling and preliminary in vivo assessment of niobium-labeled radioactive species: A proof-of-concept study. (United States)

    Radchenko, Valery; Bouziotis, Penelope; Tsotakos, Theodoros; Paravatou-Petsotas, Mari; la Fuente, Ana de; Loudos, George; Harris, Adrian L; Xanthopoulos, Stavros; Filosofov, Dmitry; Hauser, Harald; Eisenhut, Michael; Ponsard, Bernard; Roesch, Frank


    The application of radionuclide-labeled biomolecules such as monoclonal antibodies or antibody fragments for imaging purposes is called immunoscintigraphy. More specifically, when the nuclides used are positron emitters, such as zirconium-89, the technique is referred to as immuno-PET. Currently, there is an urgent need for radionuclides with a half-life which correlates well with the biological kinetics of the biomolecules under question and which can be attached to the proteins by robust labeling chemistry. (90)Nb is a promising candidate for in vivo immuno-PET, due its half-life of 14.6h and low β(+) energy of Emean=0.35MeV per decay. (95)Nb on the other hand, is a convenient alternative for longer-term ex vivo biodistribution studies, due to its longer half-life of (t½=35days) and its convenient, lower-cost production (reactor-based production). In this proof-of-principle work, the monoclonal antibody bevacizumab (Avastin(®)) was labeled with (95/90)Nb and in vitro and in vivo stability was evaluated in normal Swiss mice and in tumor-bearing SCID mice. Initial ex vivo experiments with (95)Nb-bevacizumab showed adequate tumor uptake, however at the same time high uptake in the liver, spleen and kidneys was observed. In order to investigate whether this behavior is due to instability of (⁎)Nb-bevacizumab or to the creation of other (⁎)Nb species in vivo, we performed biodistribution studies of (95)Nb-oxalate, (95)Nb-chloride and (95)Nb-Df. These potential metabolite species did not show any specific uptake, apart from bone accumulation for (95)Nb-oxalate and (95)Nb-chloride, which, interestingly, may serve as an "indicator" for the release of (90)Nb from labeled biomolecules. Concerning the initial uptake of (95)Nb-bevacizumab in non-tumor tissue, biodistribution of a higher specific activity radiolabeled antibody sample did show only negligible uptake in the liver, spleen, kidneys or bones. In-vivo imaging of a tumor-bearing SCID mouse after injection

  12. A study of the 90Zr( 3He, t) reaction at 43.4 MeV (United States)

    Fields, C. A.; Ristinen, R. A.; Samuelson, L. E.; Smith, P. A.


    Low-lying states of 90Nb have been investigated using the 90Zr( 3He, t) reaction at 43.4 MeV. In addition to the well-known π( P{1}/{2}) v (g {9}/{2}) -1and π(g {9}/{2}) v (g {9}/{2}) -1 particle-hole states, many other levels were observed. The angular distributions for the ( g{9}/{2}) 2 states are investigated using DWBA calculations using collective, OPEP, and independent tensor and spin-isospin potentials.

  13. Recent results on S = /minus/3 baryon spectroscopy from the LASS (Large Aperture Superconducting Solenoid) spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Aston, D.; Awaji, N.; Bienz, T.; Bird, F.; D' Amore, J.; Dunwoodie, W.; Endorf, R.; Fujii, K.; Hayashiii, H.; Iwata, S.


    Data demonstrating the existence of two ..cap omega../sup */minus// resonances produced in K/sup /minus//p interactions at 11 GeV/c in the LASS spectrometer are presented. The first state is seen in the ..xi../sup */degree//minus// decay channel with mass 2253 +- 13 MeV/c/sup 2/ and width 81 +- 38 MeV/c/sup 2/, and the second in the ..cap omega../sup /minus//..pi../sup +/..pi../sup /minus// system with mass 2474 +- 12 and width 72 +- 33 MeV/c/sup 2/. Inclusive cross sections corresponding to these decays corrected for unseen charge modes are estimated to be respectively 630 +- 180 and 290 +- 90 nb, respectively. 10 refs., 16 figs., 1 tab.

  14. Phenomenological model of the clavulanic acid production process utilizing Streptomyces clavuligerus

    Directory of Open Access Journals (Sweden)

    A. Baptista-Neto


    Full Text Available The kinetics of clavulanic acid production process by Streptomyces clavuligerus NRRL 3585 was studied. Experiments were carried out in a 4 liters bioreactor, utilizing 2 complex media containing glycerol as the carbon and energy source, and peptone or Samprosoy 90NB (soybean protein as nitrogen source. Temperature was kept at 28°C and the dissolved oxygen was controlled automatically at 40 % saturation value. Samples were withdrawn for determination of cell mass (only peptone medium, glycerol and product concentrations. Gas analyzers allowed on line determination of CO2 and O2 contents in the exit gas. With Samprosoy, cell mass was evaluated by determining glycerol consumption and considering the cell yield, Y X/S, as being the same for both cases. Oxygen uptake and CO2 production rates were strongly related to growth and substrate consumption, allowing determination of stoichiometric constants in relation to growth, substrate, oxygen, product and carbon dioxide.

  15. Excitation function and isomeric ratio of Tc-isotopes from the {sup 93}Nb(α, xn) reaction

    Energy Technology Data Exchange (ETDEWEB)

    Kim, K. [Department of Physics, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Kim, G.N., E-mail: [Department of Physics, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Naik, H. [Department of Physics, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Rediochemistry Division, Bhabha Atomic Research Center, Trombay, Mumbai 400085 (India); Zaman, M. [Department of Physics, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Yang, S.-C.; Song, T.-Y. [Nuclear Data Center, Korea Atomic Energy Research Institute, Daejeon 305-353 (Korea, Republic of); Guin, R.; Das, S.K. [Variable Energy Cyclotron Centre, 1/AF Bidhan Nagar, Kolkata 700064 (India)


    The excitation functions of {sup 94–96}Tc isotopes and independent isomeric ratios of {sup 93m, g}Tc, {sup 94m, g}Tc, and {sup 95m, g}Tc from the {sup 93}Nb(α, xn) reaction within the energy range below 40 MeV have been determined by using a stacked-foil activation and an off-line γ-ray spectrometric technique at the Variable Energy Cyclotron Center, Kolkota, India. The excitation function of {sup 94–96}Tc in the {sup 93}Nb(α, xn) reaction was also calculated by using the computer code TALYS 1.6. The present data are found to be in general agreement with the literature data but have similar trend with some deviation from calculated data of the TALYS 1.6 code. The isomeric ratios of {sup 93m, g}Tc, {sup 94m, g}Tc, and {sup 95m, g}Tc in the {sup 93}Nb(α, xn) reactions from the present work and literature data were compared with similar data in the {sup 93}Nb({sup 3}He, xn) and {sup 96}Mo(p, xn) reactions. In all the three reactions, the isomeric ratios increase with the increasing excitation energy. However, at all excitation energies, the isomeric ratios of {sup 93m, g}Tc, {sup 94m, g}Tc, and {sup 95m, g}Tc in the {sup 93}Nb(α, xn) and {sup 93}Nb({sup 3}He, xn) reactions are higher than those in the {sup 96}Mo(p, xn) reactions, which indicate the role of input angular momentum besides excitation energy. Above the excitation energy of 35–55 MeV, the isomeric ratios of {sup 95m, g}Tc, {sup 94m, g}Tc, and {sup 93m, g}Tc decrease in all the {sup 93}Nb(α, xn), {sup 93}Nb({sup 3}He, xn) and {sup 96}Mo(p, xn) reactions. This decreasing trend at higher excitation energy indicates the starting of pre-equilibrium reaction, which depends on the target, projectile, and type of reaction products.

  16. Fetoplacental transport of various trace elements in pregnant rat using the multitracer technique

    Energy Technology Data Exchange (ETDEWEB)

    Enomoto, Shuichi; Hirunuma, Rieko [Radioisotope Technology Division, Cyclotron Center, Institute of Physical and Chemical Research (RIKEN), Wako, Saitama (Japan)


    The placenta functions as the barrier between fetus and mother, providing means of regulation of heat exchange, respiration, nutrition, and excretion for the fetus. In this paper, the multitracer technique was applied to study the maternal transport of trace elements via the placenta to the fetus. In this experiment, the multitracer solution used contained the following nuclides: {sup 7}Be, {sup 22}Na, {sup 46}Sc, {sup 48}V, {sup 52}Mn, {sup 59}Fe, {sup 56}Co, {sup 65}Zn, {sup 67}Ga, {sup 74}As, {sup 75}Se, {sup 84}Rb, {sup 85}Sr, {sup 87}Y, {sup 88}Zr, {sup 96}Tc, {sup 101m}Rh, and {sup 103}Ru. We examined the time dependence of the uptake amounts about various elements. From these results, we observed a large difference in the time dependencies between elements and the elements were classified into three groups. Group I elements, such as Be, Sc, V, As, Y, Zr, Tc, Rh, and Ru, are transported to the placenta from the maternal blood and only accumulates in the placenta. Group II elements, such as Na, Co, Ga, Rb, and Sr, are transported to the placenta from the maternal blood and accumulate in the placenta, fetus, and amniotic fluid. Group III elements, such as Mn, Fe, Zn, and Se, are transported to the placenta from the maternal blood and mainly accumulate in the fetus. From these results, it was considered that the placenta is a highly selective filters because essential elements such as Group III elements are readily transported from the placental membrane to the growing fetus, whereas nonessential metals such as Group I elements have difficulty penetrating the placental barrier that protects the fetus from the toxic effects of these elements. (author)

  17. Study on the Volatility of Cesium in Dry Ashing Pretreatment and Dissolution of Ash by Microwave Digestion System - 13331

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Kwang-Soon; Lee, Chang Heon; Ahn, Hong-Joo; Park, Yong Joon; Song, Kyuseok [Nuclear Chemistry Research Division, Korea Atomic Energy Research Institute, Daedeok-daero 989-111, Yuseong-gu, Daejeon, 305-353 (Korea, Republic of)


    Based on the regulation of the activity concentration of Cs-137, Co-58, Co-60, Fe-55, Ni-59, Ni-63, Sr-90, Nb-94, and Tc-99, and the total alpha from the radioactive waste acceptance criteria, the measurement of the activity concentration of these nuclides in low and intermediate levels of radioactive waste such as in paper, cotton, vinyl and plastic samples was investigated. A dry ashing method was applied to obtain a concentration effect of the samples. Owing to the temperature dependence of the volatility for cesium, the temperature of 300 to 650 deg. C was examined. It was found that 450 deg. C is the optimum dry ashing temperature. After dry ashing, the produced ash was dissolved with HNO{sub 3}, HCl, and HF by a high-performance microwave digestion system. The ash sample, for the most part, was completely dissolved with 10 mL of HNO{sub 3}, 4 mL of HCl, and 0.25 mL of HF by a high-performance microwave digestion system using a nova high temperature rotor at 250 deg. C for 90 min until reaching 0.2 g. To confirm the reliability of cesium loss after the performance of the dry ashing procedure, a cesium standard solution for AAS and a Cs-137 standard solution for gamma spectrometry were added to a paper towel or a planchet of stainless steel, respectively. Cesium was measured by AAS, ICP-MS, and gamma spectrometry. The volatility of cesium did not occur until 450 deg. C ashing. (authors)

  18. LPS-induced delayed preconditioning is mediated by Hsp90 and involves the heat shock response in mouse kidney.

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    Tamás Kaucsár

    Full Text Available We and others demonstrated previously that preconditioning with endotoxin (LPS protected from a subsequent lethal LPS challenge or from renal ischemia-reperfusion injury (IRI. LPS is effective in evoking the heat shock response, an ancient and essential cellular defense mechanism, which plays a role in resistance to, and recovery from diseases. Here, by using the pharmacological Hsp90 inhibitor novobiocin (NB, we investigated the role of Hsp90 and the heat shock response in LPS-induced delayed renal preconditioning.Male C57BL/6 mice were treated with preconditioning (P: 2 mg/kg, i.p. and subsequent lethal (L: 10 mg/kg, i.p. doses of LPS alone or in combination with NB (100 mg/kg, i.p.. Controls received saline (C or NB.Preconditioning LPS conferred protection from a subsequent lethal LPS treatment. Importantly, the protective effect of LPS preconditioning was completely abolished by a concomitant treatment with NB. LPS induced a marked heat shock protein increase as demonstrated by Western blots of Hsp70 and Hsp90. NB alone also stimulated Hsp70 and Hsp90 mRNA but not protein expression. However, Hsp70 and Hsp90 protein induction in LPS-treated mice was abolished by a concomitant NB treatment, demonstrating a NB-induced impairment of the heat shock response to LPS preconditioning.LPS-induced heat shock protein induction and tolerance to a subsequent lethal LPS treatment was prevented by the Hsp90 inhibitor, novobiocin. Our findings demonstrate a critical role of Hsp90 in LPS signaling, and a potential involvement of the heat shock response in LPS-induced preconditioning.

  19. Antigenicity and diagnostic potential of vaccine candidates in human Chagas disease.

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    Shivali Gupta

    Full Text Available BACKGROUND: Chagas disease, caused by Trypanosoma cruzi, is endemic in Latin America and an emerging infectious disease in the US and Europe. We have shown TcG1, TcG2, and TcG4 antigens elicit protective immunity to T. cruzi in mice and dogs. Herein, we investigated antigenicity of the recombinant proteins in humans to determine their potential utility for the development of next generation diagnostics for screening of T. cruzi infection and Chagas disease. METHODS AND RESULTS: Sera samples from inhabitants of the endemic areas of Argentina-Bolivia and Mexico-Guatemala were analyzed in 1(st-phase for anti-T. cruzi antibody response by traditional serology tests; and in 2(nd-phase for antibody response to the recombinant antigens (individually or mixed by an ELISA. We noted similar antibody response to candidate antigens in sera samples from inhabitants of Argentina and Mexico (n=175. The IgG antibodies to TcG1, TcG2, and TcG4 (individually and TcG(mix were present in 62-71%, 65-78% and 72-82%, and 89-93% of the subjects, respectively, identified to be seropositive by traditional serology. Recombinant TcG1- (93.6%, TcG2- (96%, TcG4- (94.6% and TcG(mix- (98% based ELISA exhibited significantly higher specificity compared to that noted for T. cruzi trypomastigote-based ELISA (77.8% in diagnosing T. cruzi-infection and avoiding cross-reactivity to Leishmania spp. No significant correlation was noted in the sera levels of antibody response and clinical severity of Chagas disease in seropositive subjects. CONCLUSIONS: Three candidate antigens were recognized by antibody response in chagasic patients from two distinct study sites and expressed in diverse strains of the circulating parasites. A multiplex ELISA detecting antibody response to three antigens was highly sensitive and specific in diagnosing T. cruzi infection in humans, suggesting that a diagnostic kit based on TcG1, TcG2 and TcG4 recombinant proteins will be useful in diverse situations.

  20. A Investigation of Partially Extracted Tracers Used to Determine Myocardial Blood Flow with PET. (United States)

    Christian, Bradley Thomas

    Positron Emission Tomography (PET) provides the ability to quantitatively measure mass-specific blood flow to myocardial tissue (ml/min/g tissue). The partially extracted tracers ^{62}Cu -PTSM and two single photon emission computed tomography(SPECT) agents, teboroxime and sestamibi were studied. The latter two demonstrate the effectiveness of PET as a pharmacological tool for SPECT perfusion tracer development. The characteristics of these tracers were compared to commonly used partially extracted tracers ^{13}rm NH_3 and ^{82} Rb. Positron emitting ^{rm 94m}Tc was used to label ligands originally developed for ^{rm 99m} Tc labeling. ^{rm 94m }Tc can be produced by the bombardment of a natural molybdenum foil with an 11Mev proton beam, via the ^{94}rm Mo(p,n)^ {94m}Tc reaction. The production of ^{rm94m}Tc is accompanied by ^{92}Tc, ^ {94}Tc, ^{95} Tc, ^{rm 95m}Tc, ^{96}Tc, and ^{rm 99m}Tc due to the isotopic mixture of natural Mo. The presence of these radionuclidic impurities increase the radiation dose received by the patient and radio chemist. The elimination of these impurities was achieved by irradiating an isotopically enriched target material, ^{94}rm MoO_3. The ability to reclaim the enriched target is essential due to the high cost of the material. Recovery was accomplished by a solvent extraction technique yielding an activity recovery of 80% and target material recovery of 95%. Preliminary data was measured for the myocardial perfusion tracer ^{62}Cu -PTSM. It was found that the uptake of ^ {62}Cu-PTSM is linear for resting flows but a high degree of variability is observed at stress induced flows. This same result was found in the human studies when compared to ^{13} rm NH_3 measured myocardial perfusion values. The dynamic analysis of multiple tracers in the sequence of protocols: (1) acute canine prep ( ^{11}rm CO, ^{82 }Rb, ^{62}Cu-PTSM, ^{13}rm NH_3, ^{94m,99m}Tc-BATO, H_2 ^{14}rm O, ^{18 }FCH_3), (2) chronic canine prep ( ^{82}rm Rb, ^{13 }NH_3

  1. Spectroscopy of NIOBIUM-92, 94. (United States)

    Rumore, Mike Anthony

    The level structure of ('92,94)Nb has been studied with the reactions ('92,94)Zr(('3)He,t)('92,94)Nb, ('93)Nb(p,d)('92)Nb and ('92,94)Zr(He,p2n(gamma))92,94Nb. The resulting level schemes have been compared with shell model calculations which assume a ('88)Sr core with the protons occupying the states 2p(,1/2), 1g(,9/2) and the neutrons in the 2d(,5/2), 1g(,7/2) , 2d(,3/2) and 3s(,1/2) states. The residual interaction in the ('92)Nb configurations ((pi)g(,9/2), (nu)d(,5/2)) and. (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI). has been determined and compared with the predictions from a zero-range interaction ((delta)-force). Comparisons have also been made with the. (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI). configuration in ('90)Nb. Angular distributions were obtained between 6.0 to 55.0 degrees for the ('93)Nb(p,d)('92)Nb reaction. The DWBA analysis was carried out using adiabatic deuteron potentials and spectroscopic factors were extracted. States belonging to various configurations were determined. Spectroscopic factors belonging to the ground state multiplet ((pi)g(,9/2),(nu)d(,5/2)) were compared with shell model predictions. Discrepancies between the spectroscopic factors measured using the (p,d) reaction and those measured previously using the (d,t) reaction were attributed to finite range corrections and the neutron bound state geometry. Much configuration mixing has been found in most ('92)Nb states above 1.0 MeV in excitation energy. The (('3)He,t) charge exchange reactions were used to determine the spin and parity of states belonging to the previously mentioned configurations. Data were obtained for scattering angles from 5.0 to 45.0 degrees and the measured angular distributions were analyzed using a microscopic OPEP interaction between the target and the projectile. The isobaric ground state was observed at an excitation energy of 9010 keV for ('92)Nb. Th ('92,94)Zr(('3)He,p2n(gamma))('92,94)Nb (gamma) -(gamma) coincidence data were