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  1. Theory of High-TC Superconductivity: Accurate Predictions of TC

    NASA Astrophysics Data System (ADS)

    Harshman, Dale; Fiory, Anthony

    2012-02-01

    The superconducting transition temperatures of high-TC compounds based on copper, iron, ruthenium and certain organic molecules is discovered to be dependent on bond lengths, ionic valences, and Coulomb coupling between electronic bands in adjacent, spatially separated layers [1]. Optimal transition temperature, denoted as TC0, is given by the universal expression kBTC0 = e^2λ/lζ; l is the spacing between interacting charges within the layers, ζ is the distance between interacting layers and λ is a universal constant, equal to about twice the reduced electron Compton wavelength (suggesting that Compton scattering plays a role in pairing). Non-optimum compounds in which sample degradation is evident typically exhibit TC < TC0. For the 31+ optimum compounds tested, the theoretical and experimental TC0 agree statistically to within ± 1.4 K. The elemental high-TC building block comprises two adjacent and spatially separated charge layers; the factor e^2/ζ arises from Coulomb forces between them. The theoretical charge structure representing a room-temperature superconductor is also presented. * 1. doi:10.1088/0953-8984/23/29/295701

  2. GASIFICATION TEST RUN TC06

    SciTech Connect

    Southern Company Services, Inc.

    2003-08-01

    This report discusses test campaign TC06 of the Kellogg Brown & Root, Inc. (KBR) Transport Reactor train with a Siemens Westinghouse Power Corporation (Siemens Westinghouse) particle filter system at the Power Systems Development Facility (PSDF) located in Wilsonville, Alabama. The Transport Reactor is an advanced circulating fluidized-bed reactor designed to operate as either a combustor or a gasifier using a particulate control device (PCD). The Transport Reactor was operated as a pressurized gasifier during TC06. Test run TC06 was started on July 4, 2001, and completed on September 24, 2001, with an interruption in service between July 25, 2001, and August 19, 2001, due to a filter element failure in the PCD caused by abnormal operating conditions while tuning the main air compressor. The reactor temperature was varied between 1,725 and 1,825 F at pressures from 190 to 230 psig. In TC06, 1,214 hours of solid circulation and 1,025 hours of coal feed were attained with 797 hours of coal feed after the filter element failure. Both reactor and PCD operations were stable during the test run with a stable baseline pressure drop. Due to its length and stability, the TC06 test run provided valuable data necessary to analyze long-term reactor operations and to identify necessary modifications to improve equipment and process performance as well as progressing the goal of many thousands of hours of filter element exposure.

  3. Tc7, a Tc1-hitch hiking transposon in Caenorhabditis elegans.

    PubMed Central

    Rezsohazy, R; van Luenen, H G; Durbin, R M; Plasterk, R H

    1997-01-01

    We have found a novel transposon in the genome of Caenorhabditis elegans. Tc7 is a 921 bp element, made up of two 345 bp inverted repeats separated by a unique, internal sequence. Tc7 does not contain an open reading frame. The outer 38 bp of the inverted repeat show 36 matches with the outer 38 bp of Tc1. This region of Tc1 contains the Tc1-transposase binding site. Furthermore, Tc7 is flanked by TA dinucleotides, just like Tc1, which presumably correspond to the target duplication generated upon integration. Since Tc7 does not encode its own transposase but contains the Tc1-transposase binding site at its extremities, we tested the ability of Tc7 to jump upon forced expression of Tc1 transposase in somatic cells. Under these conditions Tc7 jumps at a frequency similar to Tc1. The target site choice of Tc7 is identical to that of Tc1. These data suggest that Tc7 shares with Tc1 all the sequences minimally required to parasitize upon the Tc1 transposition machinery. The genomic distribution of Tc7 shows a striking clustering on the X chromosome where two thirds of the elements (20 out of 33) are located. Related transposons in C. elegans do not show this asymmetric distribution. PMID:9321656

  4. Graphoepitaxial high-Tc SQUIDs

    NASA Astrophysics Data System (ADS)

    Faley, M. I.; Meertens, D.; Poppe, U.; Dunin-Borkowski, R. E.

    2014-05-01

    The fabrication process and physical properties of graphoepitaxially engineered high-Tc direct current superconducting quantum interferometer devices (DC SQUIDs) are studied. Double buffer layers, each comprising a graphoepitaxial seed layer of YBa2Cu3O7-x and an epitaxial blocking layer of SrTiO3, were deposited over textured step edges on (001) surfaces of MgO substrates. Scanning electron microscopy and high-resolution transmission electron microscopy were used to investigate the microstructural properties of DC SQUIDs with graphoepitaxial Josephson junctions. Both direct coupled and inductively coupled high-Tc DC SQUIDs with graphoepitaxial step edge junctions and flux transformers were studied.

  5. Superconducting bolometers: high-Tc and low-Tc

    NASA Astrophysics Data System (ADS)

    Richards, Paul L.

    1991-07-01

    A description is given of recent work at Berkeley on superconducting detectors and mixers for infrared and millimeter wavelengths. The first report is a review article which summarizes the status of development of superconducting components for infrared and millimeter wave receivers. Next, a report is given on measurements and theoretical modeling of the absorptivity (surface resistance) of high quality epitaxial films of the high-Tc superconductor YBCO from 750 GHz to 21 THz. The next report describes measurements of the thermal boundary resistance between YBCO films and various substrates. This resistance is much larger than expected from the acoustic impedance mismatch model and gives a thermal time constant in the nanosecond range for typical YBCO films. Reports are also included on the design and experimental performance of two different types of high-Tc bolometric detectors. One is a conventional bolometer with a gold-black absorber. The other is an antenna coupled microbolometer. The properties of a low-Tc microbolometer are also described. The last reports describe accurate measurements and also theoretical modeling of an SIS quasi-particle waveguide mixer for W-band which uses very high quality Ta junctions. The best mixer noise is only 1.3 times the quantum limit. Both the mixer gain and the noise are in quantitative agreement with the quantum theory.

  6. Mental Health and the TC. Chapter 5.

    ERIC Educational Resources Information Center

    Acampora, Alfonso P., Ed.; Nebelkopf, Ethan, Ed.

    This document contains 19 papers from the ninth World Conference of Therapeutic Communities (TCs) that deal with the interface between the mental health establishments and the TC. Papers include: (1) "Psychiatry and the TC" (Jerome Jaffe); (2) "The Chemical Brain" (Sidney Cohen); (3) "Where Does the TC Fail?" (Ab…

  7. PREFACE: 13th IMEKO TC17-TC7 Joint Symposium

    NASA Astrophysics Data System (ADS)

    Khan, Sanowar

    2010-04-01

    'Without Measurement No Science, Without Science No Measurement' The 13th IMEKO (International Measurement Confederation) TC1-TC7 Joint Symposium was held at City University London, UK from 1-3 September 2010. For the first time this Symposium also included the involvement of IMEKO Technical Committee 13 (TC13) - Measurements in Biology and Medicine. This brings an added dimension to the Symposium in London since the area of measurement science and technology in biology and medicine is an important and a fast growing one. The Symposium was organized by the City University London (www.city.ac.uk) in collaboration with the Institute of Physics (IOP), UK (www.iop.org). The work of this Symposium is reported in this volume. The scope of the Symposium included the main topics covered by the above Technical Committees - education and training in measurement and instrumentation (TC1), measurement science (TC7) and measurements in biology and medicine. These themes underpinned the strap line of the Symposium, 'Without Measurement No Science, Without Science No Measurement' with the highest number of contributions from the measurement science area. The thematic areas were led by invited presentations from each of the areas by eminent speakers. The Symposium provided a useful forum for experts working in these areas for sharing and exchanging their work and ideas. The Symposium attracted participants from many countries of the world including the United States, Japan, Russia and Ukraine. In total over sixty papers are included in the volume and they are presented under the above three key thematic areas. Each paper was independently peer-reviewed by two reviewers from a distinguished international panel. The organizers of the Symposium, City University London have pioneered the establishment of measurement and instrumentation as an academic discipline in the UK through the work of Professor Ludwik Finkelstein who was for many years Chairman of TC1 and a founding member of TC

  8. Giant electrocaloric effect around Tc.

    PubMed

    Rose, Maimon C; Cohen, R E

    2012-11-02

    We use molecular dynamics with a first-principles-based shell model potential to study the electrocaloric effect (ECE) in lithium niobate, LiNbO(3), and find a giant electrocaloric effect along a line passing through the ferroelectric transition. With an applied electric field, a line of maximum ECE passes through the zero field ferroelectric transition, continuing along a Widom line at high temperatures with increasing fields, and along the instability that leads to homogeneous ferroelectric switching below T(c) with an applied field antiparallel to the spontaneous polarization. This line is defined as the minimum in the inverse capacitance under an applied electric field. We investigate the effects of pressure, temperature and an applied electric field on the ECE. The behavior we observe in LiNbO(3) should generally apply to ferroelectrics; we therefore suggest that the operating temperature for refrigeration and energy scavenging applications should be above the ferroelectric transition region to obtain a large electrocaloric response. The relationship between T(c), the Widom line, and homogeneous switching should be universal among ferroelectrics, relaxors, multiferroics, and the same behavior should be found under applied magnetic fields in ferromagnets.

  9. Tc-99 Ion Exchange Resin Testing

    SciTech Connect

    Valenta, Michelle M.; Parker, Kent E.; Pierce, Eric M.

    2010-08-01

    Pacific Northwest National Laboratory was contracted by CHPRC to evaluate the release of 99Tc from spent resin used to treat water from well 299-W15-765 and stored for several years. The key questions to be answered are: 1) does 99Tc readily release from the spent ion exchange resin after being in storage for several years; 2) if hot water stripping is used to remove the co-contaminant carbon tetrachloride, will 99Tc that has been sequestered by the resin be released; and 3) can spent resin be encapsulated into a cementitious waste form; if so, how much 99Tc would be released from the weathering of the monolith waste form? The results from the long term stability leach test results confirm that the resin is not releasing a significant amount of the sequestered 99Tc, evident by the less than 0.02% of the total 99Tc loaded being identified in the solution. Furthermore, it is possible that the measured 99Tc concentration is the result of 99Tc contained in the pore spaces of the resin. In addition to these results, analyses conducted to examine the impact of hot water on the release of 99Tc suggest that only a small percentage of the total is being released. This suggest that hot water stripping to remove carbon tetrachloride will not have a significant affect on the resin’s ability to hold-on to sequestered 99Tc. Finally, encapsulation of spent resin in a cementitious material may be a viable disposal option, but additional tests are needed to examine the extent of physical degradation caused by moisture loss and the effect this degradation process can have on the release of 99Tc.

  10. Tc-99m Labeled carrier for imaging

    DOEpatents

    Henze, Eberhard

    1984-01-01

    Novel radionuclide imaging agents, having particular application for lymphangiography are provided by non-covalently binding Tc-99m to a pharmaceutically acceptable cross-linked polysaccharide. Upon injection of the Tc-99m labeled polysaccharide into the blood stream, optimum contrast can be obtained within one hour.

  11. Scintillating 99Tc Selective Ion Exchange Resins

    SciTech Connect

    Mitchell Greenhalgh; Richard D. Tillotson

    2012-07-01

    Scintillating technetium (99Tc) selective ion exchange resins have been developed and evaluated for equilibrium capacities and detection efficiencies. These resins can be utilized for the in-situ concentration and detection of low levels of pertechnetate anions (99TcO4-) in natural waters. Three different polystyrene type resin support materials were impregnated with varying amounts of tricaprylmethylammonium chloride (Aliquat 336) extractant, several different scintillating fluors and wavelength shifters. The prepared resins were contacted batch-wise to equilibrium over a wide range of 99TcO4- concentrations in natural water. The measured capacities were used to develop Langmuir adsorption isotherms for each resin. 99Tc detection efficiencies were determined and up to 71.4 ± 2.6% was achieved with some resins. The results demonstrate that a low level detection limit for 99TcO4- in natural waters can be realized.

  12. High-Tc and low-Tc dc SQUID electronics

    NASA Astrophysics Data System (ADS)

    Drung, Dietmar

    2003-12-01

    Superconducting quantum interference devices (SQUIDs) are commonly operated in a flux-locked loop (FLL). The SQUID electronics amplifies the small SQUID signal to an acceptable level without adding noise, and it linearizes the transfer function of the SQUID in order to provide sufficient dynamic range. In this paper, the fundamentals of SQUID readout are reviewed including a discussion of preamplifier noise. The basic FLL concepts, direct readout and flux modulation readout, are discussed both with dc bias and bias reversal. Alternative readout concepts such as additional positive feedback (APF), two-stage SQUIDs, SQUID series arrays, relaxation oscillation SQUIDs and digital SQUIDs are briefly described. The FLL dynamics are discussed on the basis of a simple model with finite loop delay. It is shown that with optimized SQUID electronics a system bandwidth of ap18 MHz and a corresponding slew rate of ap8 PHgr0 µs-1 are possible. A novel FLL scheme involving a Smith predictor is presented which allows one to increase the FLL bandwidth to about 100 MHz. The theoretical predictions are experimentally checked using a high-speed SQUID electronics prototype with a small-signal bandwidth of 300 MHz. Methods for increasing the dynamic range of SQUID systems are described: flux-quanta counting and dynamic field compensation (DFC). With DFC, the residual magnetic field at the SQUID can be kept close to zero even if the device is moved in the Earth's field. Therefore, the noise level of a high-Tc magnetometer measured inside a magnetically shielded room (60 fT Hz-1/2 with a 1/f corner at 2 Hz) remained unchanged after moving the device in the magnetic field outside the room (60 µT dc plus 0.8 µT peak-to-peak power line interference).

  13. Behavior of reduced 99/Tc and 99/Tc organic complexes on Hanford soil

    SciTech Connect

    Franz, J.A.; Martin, L.Y.; Wiggins, D.J.

    1982-02-01

    Both synthetically and naturally derived organic complexing agents in soil have been found in other studies to accelerate the rate of migration of specific radionuclides. In an effort to aid in the development of comprehensive plans for the disposal of low-level waste, the effect of organic complexing agents on the transport properties of /sup 99/Tc, a long-lived constituent of radioactive waste, was examined. The effect of ethylenediaminetetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTPA), and sodium citrate on the mobility of reduced Tc species was examined from two aspects: first, by techniques of desorption from soil in which reduced, sorbed Tc was exposed to solutions of organic ligands; and second, by exposure of synthetic Tc-organic complexes to soils. Only a slight desorption of reduced Tc from Hanford soil by EDTA was found to occur in 10-day desorption tests. However, when synthetic EDTA and DTPA complexes of reduced Tc were exposed to soil under similar conditions, only a slight amount of Tc was sorbed by the soil. This comparison clearly shows that at least one type of test did not reach equilibrium in the 10-day time period allowed. Although the effects of these complexants at equilibrium cannot be quantified from these data, it is obvious that they can have large effects on the mobility of reduced Tc. Desorption tests of reduced Tc from Hanford soil by citrate solutions showed definite indications of desorption only at a relatively high (0.01 M) citrate concentrations. Results with synthetic Tc(IV) and Tc(V) citrate complexes indicate the Tc(V) citrate complex to be strongly sorbed, while the Tc(IV) citrate complex was sorbed only slightly.

  14. Direct 99m Tc labeling of Herceptin (trastuzumab) by 99m Tc(I) tricarbonyl ion.

    PubMed

    Chen, Wan-Jou; Yen, Chao-Liang; Lo, Su-Tang; Chen, Kuo-Ting; Lo, Jem-Mau

    2008-03-01

    By simply incubating Herceptin (trastuzumab) with [99m Tc(CO)3(OH2)3]+ ion in saline, a significant yield of 99m Tc-labeled trastuzumab was found to be achievable. The effective labeling may be based on that trastuzumab is inherent with endogenous histidine group to which 99m Tc(I) tricarbonyl ion can be strongly bound. For practical 99m Tc labeling processing, trastuzumab was purified beforehand from the commercial product, Herceptin (Genentech) via size exclusion chromatography to remove the excipient, alpha-histidine and a high-labeled yield could be obtained by incubating the purified trastuzumab with [99m Tc(CO)3(OH2)3]+. Retention of bioactivity of the 99m Tc(I)-labeled trastuzumab was validated using a cell binding test.

  15. Tc1/Tc2 imbalance in the peripheral blood of patients with recurrent genital herpes.

    PubMed

    Deng, Yunhua; Yang, Dongliang; Chen, Xingping; Chen, Yinling

    2006-01-01

    In order to investigate the IFN-gamma and IL-4 expression of CD8+ T lymphocytes in the peripheral blood from patients with recurrent genital herpes (RGH) at different clinical periods and their relationship with the pathogenesis of RGH, flow cytometry was used to detect the intracellular cytokines (IFN-gamma and IL-4) of CD8+ T lymphocytes in the peripheral blood of 30 patients with RGH at acute period, 20 patients with RGH at recovery period and 15 healthy volunteers. The results showed that RGH patients at acute period had a lower percentage of Tc1 subsets in peripheral blood than that of healthy controls (P < 0.001), especially a remarkable decreased percentage of Tc1 subsets (P < 0.001) among those RGH patients with recurrent number more than 3 in the recent half a year. Tc1/Tc2 ratio in the RGH patients at acute period was significantly decreased as compared with normal control group (P < 0.05). The recurrent number of acute patients in the recent half a year was significantly correlated with the percentage of Tc1 subsets and the ratio of Tc1/Tc2 (P < 0.05). A decreased percentage of Tc1 subsets was found among the RGH patients with recurrent number more than 3 in the recent half a year at recovery period in comparison with healthy volunteers (P < 0.05), and it was significantly correlated with the recurrent number in the recent half a year (P < 0.05). It is concluded that there are Tc1/Tc2 imbalance and a low level of Tc1 subsets in RGH patients who are relapsing repeatedly in the near period. The low level of Tc1 subsets may be an important factor for the recurrence of RGH and the reactivation of latent herpesvirus infection.

  16. Technetium Removal Using Tc-Goethite Coprecipitation

    SciTech Connect

    Um, Wooyong; Wang, Guohui; Jung, Hun Bok; Peterson, Reid A.

    2013-11-18

    This report describes the results from laboratory tests performed at Pacific Northwest National Laboratory for the U.S. Department of Energy (DOE) EM-31 Support Program (EMSP) subtask, “Low temperature waste forms coupled with technetium removal using an alternative immobilization process such as Fe(II) treated-goethite precipitation” to increase our understanding of 99Tc long-term stability in goethite mineral form and the process that controls the 99Tc(VII) reduction and removal by the final Fe (oxy)hydroxide forms. The overall objectives of this task were to 1) evaluate the transformation process of Fe (oxy)hydroxide solids to the more crystalline goethite (α-FeOOH) mineral for 99Tc removal and 2) determine the mechanism that limits 99Tc(IV) reoxidation in Fe(II)-treated 99Tc-goethite mineral and 3) evaluate whether there is a long-term 99Tcoxidation state change for Tc sequestered in the iron solids.

  17. Renal uptakes of 99mTc-MAG3, 99mTc-DTPA, and 99mTc-DMSA in rabbits with unilateral ureteral obstruction.

    PubMed

    Lee, Won Guk; Kim, Joong-Hyun; Kim, Jong Min; Shim, Kyung Mi; Kang, Seong Soo; Chae, Hong In; Choi, Seok Hwa

    2010-01-01

    Renal function measurements using (99m)Tc-DTPA and (99m)Tc-MAG(3) dynamic scintigraphs were compared to those obtained using (99m)Tc-DMSA static scintigraphy. Eighteen experimental rabbits were randomly divided into (99m)Tc-DTPA-, (99m)Tc-MAG(3)-, and (99m) Tc-DMSA-injected groups. Experimental unilateral renal damage was induced by ligating a unilateral right ureter in 18 rabbits. Scintigraphic images were obtained at 2 and 5 h after intravenous injection of (99m)Tc-DMSA, or immediately after administration of (99m)Tc-DTPA or (99m)Tc-MAG(3). For the dynamic images using (99m)Tc-DTPA and (99m)Tc-MAG(3), rapid sequential images were obtained every 2 s for 30 images up to 1 min. The three groups presented different relative renal functions between the left normal and the right abnormal kidneys at 1, 2, 3, and 4 weeks post-ligation (p<0.05). However, the between-group comparisons showed no significant differences at any time. These results suggest that dynamic images of (99m)Tc-DTPA and (99m)Tc-MAG(3) can be used to measure the relative renal function in place of the static image of (99m)Tc-DMSA.

  18. PREFACE: 2014 Joint IMEKO TC1-TC7-TC13 Symposium: Measurement Science Behind Safety and Security

    NASA Astrophysics Data System (ADS)

    Sousa, João A.; Ribeiro, Álvaro S.; Filipe, Eduarda

    2015-02-01

    The 2014 Joint IMEKO (International Measurement Confederation) TC1-TC7-TC13 Symposium was organized by RELACRE - Portuguese Association of Accredited Laboratories and the Portuguese Society for Metrology, on 3-5 September 2014. The work of this symposium is reported in this volume. The scope of the symposium includes the main topics covered by the above Technical Committees: - TC1 Education and Training in measurement and Instrumentation - TC7 Measurement Science - TC13 Measurements in Biology and Medicine The effort towards excellence of previous events, in this well established series, is maintained. There has been a special focus on measurement science behind safety and security, with the aim of highlighting the interdisciplinary character of measurement science and the importance of metrology in our daily lives. The discussion was introduced by keynote lectures on measurement challenges in biometrics, health monitoring and social sciences, to promote useful interactions with scientists from different disciplines. The Symposium was attended by experts working in these areas from 18 countries, including USA, Japan and China, and provided a useful forum for them to share and exchange their work and ideas. In total over fifty papers are included in the volume, organized according to the presentation sessions. Each paper was independently peer-reviewed by two reviewers from a distinguished international panel. The Symposium was held in Funchal, capital of Madeira Islands, known as the Atlantic Pearl. This wonderful Atlantic archipelago, formed by Madeira and Porto Santo islands, discovered in the 14th century, was chosen to host the 2014 IMEKO TC1-TC7-TC13 Joint Symposium ''Measurement Science behind Safety and Security''. It was the first territory discovered by the Portuguese sailors, when set out to discover a new world, in an epic journey where instrumentation and quality of measurement played a central role in the success of the enterprise, and gave an

  19. Tc-Glutathione Complex (Tc -GSH) : Labelling, Chemical Characterization and Biodistribution in Rats

    PubMed Central

    Moretti, J. L.; Weinmann, P.; Senekowitsch-Schmidtke, R.; Ercan, M. T.

    1999-01-01

    The chemical structure of 99mTc-GSH has been estabilished using the 99Tc isotope. Labeling of glutathione with technetium in the presence of stanous chloride gave a high yield result. In a comparative study between 99Tc and 99Tc glutathione, the Tc-GSH complex obtained was purified and characterized by uv, visible spectroscopy, HPLC, Biogel chromatography, mass and NMR spectroscopy. Stoichiometric analysis showed a 2 : 1 molar ratio of GSH/Tc for the reaction. The molecular mass assessed by mass spectroscopy was 727 Da corresponding to an oxo(bis) glutathione technetate. NMR studies demonstrated that each glutathione molecule was coordinated to technetium via cysteinyl sulfur and nitrogen atoms. The biodistribution of the complex was studied in normal rats. Blood clearance was rapid during the first hour involving a biexponential curve ( t1/2 (1) : 50 min, t1/2 (2) : 400 min ). No radioactive accumulation was found in any specific organ except kidney and bladder. All the activity excreted was found unchanged in urine. In conclusion, Tc-GSH displayed an anionic dimer form as GSH-Tc-GSH. We assume that the complex is a tetradentate (2N,2S) complex containing a pentavalent technetium coordinated by two thiol and nitrogen atoms of both GSH ligands, and an apical oxo group. PMID:18475909

  20. Insights into Stabilization of the 99TcVO Core for Synthesis of 99TcVO Compounds

    SciTech Connect

    McGregor, Donna; Burton-Pye, Benjamin P.; Lukens, Wayne W.; Howell, Robertha C.; Francesconi, Lynn C.

    2014-01-01

    Synthesis of technetium-99 (99Tc; t1/2: 2.1 105 years, max: 253 keV) materials is of importance in studies of the nuclear fuel cycle where Tc is a major fission product (6percent thermal yield from 235U and 239Pu), in understanding radioactive tank waste composition, and in identifying 99mTc compounds for nuclear medicine imaging. One of the most useful synthetic starting materials, (NBu4)TcOCl4, is susceptible to disproportionation in water to form TcO4 and TcIV species, especially TcO2 2H2O. This unwanted reaction is especially problematic when working with ligands bearing hard donor atoms, such as oxygen, where the stability with the soft TcV=O3+ core may be low. Polyoxometalates (POMs) are such ligands. They possess defect sites with four hard oxygen atoms and show low (ca. 108) stability constants with transition metals. Tc complexes of POMs are molecular-level models for Tc metal oxide solid-state materials and can provide information on coordination and redox environments of metal oxides that stabilize low-valent Tc. In order to synthesize pure Tc POM complexes [TcVO(1-P2W17O61)]7 (TcVO-1) and [TcVO(2-P2W17O61)]7 (TcVO-2) from (NBu4)TcOCl4, we have identified strategies that minimize formation of TcIV species and optimize the formation of pure TcV species. The parameters that we consider are the amount of ethylene glycol, which is employed as a transfer ligand to prevent hydrolysis of (NBu4)TcOCl4, and the precipitating agent. The TcIV species that contaminates the non-optimized syntheses is likely a TcIV -oxido-bridged dimer [TcIV-(-O)2-TcIV]. We also employ a novel procedure where the 2 ligand is photoactivated and reduced (in the presence of a sacrificial electron donor) to subsequently reduce TcVIIO4 to an isolatable TcVO-2 product that is remarkably free of TcIV.

  1. Research progress of Tc1/Mariner superfamily.

    PubMed

    Dan, Shen; Cai, Chen; Saisai, Wang; Wei, Chen; Bo, Gao; Chengyi, Song

    2017-01-20

    With the rapid improvement of sequencing techniques, more and more genome annotations reveal the transposons are the important components of most genomes and present on almost all organisms. Among them, the Tc1/Mariner superfamily represents the most widespread DNA transposons. Until now, fourteen active Tc1/Mariner transposons (Minos, Mos1, etc.) have been identified and some highly active artificial transposons have been created through molecular reconstruction, such as Sleeping Beauty (SB). The transposons such as SB and Mos1 have been widely used as gene transfer vectors in the fields of transgenosis, gene trapping and gene therapy. In this review, we summarize the structure, classification, distributions, transposition mechanism and excavations of active members of Tc1/Mariner as well as its application in the fields of transgenesis, gene trapping and gene therapy.

  2. CTLA-4 (CD152) enhances the Tc17 differentiation program.

    PubMed

    Pick, Jonas; Arra, Aditya; Lingel, Holger; Hegel, J Kolja; Huber, Magdalena; Nishanth, Gopala; Jorch, Gerhard; Fischer, Klaus-Dieter; Schlüter, Dirk; Tedford, Kerry; Brunner-Weinzierl, Monika C

    2014-07-01

    Although CD8(+) T cells that produce IL-17 (Tc17 cells) have been linked to host defense, Tc17 cells show reduced cytotoxic activity, which is the characteristic function of CD8(+) T cells. Here, we show that CTLA-4 enhances the frequency of IL-17 in CD8(+) T cells, indicating that CTLA-4 (CD152) specifically promotes Tc17 differentiation. Simultaneous stimulation of CTLA-4(+/+) and CTLA-4(-/-) T cells in cocultures and agonistic CTLA-4 stimulation unambiguously revealed a cell-intrinsic mechanism for IL-17 control by CTLA-4. The quality of CTLA-4-induced Tc17 cells was tested in vivo, utilizing infection with the facultative intracellular bacterium Listeria monocytogenes (LM). Unlike CTLA-4(+/+) Tc17 cells, CTLA-4(-/-) were nearly as efficient as Tc1 CTLA-4(+/+) cells in LM clearance. Additionally, adoptively transferred CTLA-4(-/-) Tc17 cells expressed granzyme B after rechallenge, and produced Tc1 cytokines such as IFN-γ and TNF-α, which strongly correlate with bacterial clearance. CTLA-4(+/+) Tc17 cells demonstrated a high-quality Tc17 differentiation program ex vivo, which was also evident in isolated IL-17-secreting Tc17 cells, with CTLA-4-mediated enhanced upregulation of Tc17-related molecules such as IL-17A, RORγt, and IRF-4. Our results show that CTLA-4 promotes Tc17 differentiation that results in robust Tc17 responses. Its inactivation might therefore represent a central therapeutic target to enhance clearance of infection.

  3. Telecom 2-B and 2-C (TC2B and TC2C)

    NASA Technical Reports Server (NTRS)

    Dulac, J.; Alvarez, H.

    1991-01-01

    The DSN (Deep Space Network) mission support requirements for Telecom 2-B and 2-C (TC2B and TC2C) are summarized. These Telecom missions will provide high-speed data link applications, telephone, and television service between France and overseas territories as a follow-on to TC2A. Mission objectives are outlined and the DSN support requirements are defined through the presentation of tables and narratives describing the spacecraft flight profile; DSN support coverage; frequency assignments; support parameters for telemetry, command and support systems; and tracking support responsibility.

  4. Adolescent Services & the TC. Chapter 6.

    ERIC Educational Resources Information Center

    Acampora, Alfonso P., Ed.; Nebelkopf, Ethan, Ed.

    This document contains seven papers from the ninth World Conference of Therapeutic Communities (TCs) that deal with adolescent clients and TCs. Papers include: (1) Preliminary Consideration on "Adolescence and the TC" (David Deitch); (2) "Daytop's Full Service Adolescent Treatment Program" (Charles Devlin and Lois Morris); (3)…

  5. NDP kinase reactivity towards 3TC nucleotides.

    PubMed

    Kreimeyer, A; Schneider, B; Sarfati, R; Faraj, A; Sommadossi, J P; Veron, M; Deville-Bonne, D

    2001-05-01

    Nucleoside diphosphate (NDP) kinase is usually considered as the enzyme responsible for the last step of the cellular phosphorylation pathway leading to the synthesis of biologically active triphospho-derivatives of nucleoside analogs used in antiviral therapies and in particular in the treatment of AIDS. NDP kinase lacks specificity for the nucleobase and can use as substrate both ribo- or 2'-deoxyribonucleotides. However, only nucleoside analogs with a sugar moiety in the D-configuration (e.g. 3'-deoxy-3'-azidothymidine (AZT), 2',3'-didehydro-2',3'-dideoxythymidine (d4T)) have so far been analyzed as substrates of NDP kinase. In contrast, beta-L-2',3'-dideoxy-3'-thiacytidine (3TC), also called lamivudine, is a nucleoside analog that is now widely used in AIDS therapy and has a sugar moiety in the L-configuration. Using protein fluorescence to monitor the phosphotransfer between the enzyme and the nucleotide derivative at the presteady state, we have studied the reactivity of 3TC triphosphate and of other L-dideoxynucleotides with NDP kinase. We found that L-dideoxynucleoside triphosphates have a poor affinity for NDP kinase and that the catalytic efficiency of the phosphorylation of L-dideoxyderivatives is very low as compared with their D-enantiomers. We discuss these results using a computer model of 3TC diphosphate bound to the NDP kinase active site. NDP kinase may not seem to be the major enzyme phosphorylating 3TC-DP, in contrast to current opinion.

  6. Women, Family Systems & the TC. Chapter 8.

    ERIC Educational Resources Information Center

    Acampora, Alfonso P., Ed.; Nebelkopf, Ethan, Ed.

    This document contains 11 papers from the ninth World Conference of Therapeutic Communities (TCs) that deal with women's issues, family systems, and the TC. Papers include: (1) "Families in the Eighties" (Cecil Williams); (2) "Women, Work & Substance Abuse" (Lois Morris); (3) "The National Federation of Parents"…

  7. Adoptive transfer of Tc1 or Tc17 cells elicits antitumor immunity against established melanoma through distinct mechanisms.

    PubMed

    Yu, Yu; Cho, Hyun-Ii; Wang, Dapeng; Kaosaard, Kane; Anasetti, Claudio; Celis, Esteban; Yu, Xue-Zhong

    2013-02-15

    Adoptive cell transfer (ACT) of ex vivo-activated autologous tumor-reactive T cells is currently one of the most promising approaches for cancer immunotherapy. Recent studies provided some evidence that IL-17-producing CD8(+) (Tc17) cells may exhibit potent antitumor activity, but the specific mechanisms have not been completely defined. In this study, we used a murine melanoma lung-metastasis model and tested the therapeutic effects of gp100-specific polarized type I CD8(+) cytotoxic T (Tc1) or Tc17 cells combined with autologous bone marrow transplantation after total body irradiation. Bone marrow transplantation combined with ACT of antitumor (gp100-specific) Tc17 cells significantly suppressed the growth of established melanoma, whereas Tc1 cells induced long-term tumor regression. After ACT, Tc1 cells maintained their phenotype to produce IFN-γ, but not IL-17. However, although Tc17 cells largely preserved their ability to produce IL-17, a subset secreted IFN-γ or both IFN-γ and IL-17, indicating the plasticity of Tc17 cells in vivo. Furthermore, after ACT, the Tc17 cells had a long-lived effector T cell phenotype (CD127(hi)/KLRG-1(low)) as compared with Tc1 cells. Mechanistically, Tc1 cells mediated antitumor immunity primarily through the direct effect of IFN-γ on tumor cells. In contrast, despite the fact that some Tc17 cells also secreted IFN-γ, Tc17-mediated antitumor immunity was independent of the direct effects of IFN-γ on the tumor. Nevertheless, IFN-γ played a critical role by creating a microenvironment that promoted Tc17-mediated antitumor activity. Taken together, these studies demonstrate that both Tc1 and Tc17 cells can mediate effective antitumor immunity through distinct effector mechanisms, but Tc1 cells are superior to Tc17 cells in mediating tumor regression.

  8. Inverse correlation between quasiparticle mass and Tc in a cuprate high-Tc superconductor

    PubMed Central

    Putzke, Carsten; Malone, Liam; Badoux, Sven; Vignolle, Baptiste; Vignolles, David; Tabis, Wojciech; Walmsley, Philip; Bird, Matthew; Hussey, Nigel E.; Proust, Cyril; Carrington, Antony

    2016-01-01

    Close to a zero-temperature transition between ordered and disordered electronic phases, quantum fluctuations can lead to a strong enhancement of electron mass and to the emergence of competing phases such as superconductivity. A correlation between the existence of such a quantum phase transition and superconductivity is quite well established in some heavy fermion and iron-based superconductors, and there have been suggestions that high-temperature superconductivity in copper-oxide materials (cuprates) may also be driven by the same mechanism. Close to optimal doping, where the superconducting transition temperature Tc is maximal in cuprates, two different phases are known to compete with superconductivity: a poorly understood pseudogap phase and a charge-ordered phase. Recent experiments have shown a strong increase in quasiparticle mass m* in the cuprate YBa2Cu3O7-δ as optimal doping is approached, suggesting that quantum fluctuations of the charge-ordered phase may be responsible for the high-Tc superconductivity. We have tested the robustness of this correlation between m* and Tc by performing quantum oscillation studies on the stoichiometric compound YBa2Cu4O8 under hydrostatic pressure. In contrast to the results for YBa2Cu3O7-δ, we find that in YBa2Cu4O8, the mass decreases as Tc increases under pressure. This inverse correlation between m* and Tc suggests that quantum fluctuations of the charge order enhance m* but do not enhance Tc. PMID:27034989

  9. Development of Tc(IV)-Incorporated Fe Minerals to Enhance 99Tc Retention in Glass Waste Form

    SciTech Connect

    Um, Wooyong; Luksic, Steven A.; Wang, Guohui; Kim, Dong-Sang; Schweiger, Michael J.; Hrma, Pavel R.; Kruger, Albert A.

    2015-03-17

    Iron minerals have been considered to be good hosts for Tc immobilization because the Tc(IV) ion substitutes for Fe(III) in the crystal structure of the Fe oxide due to similarities in (1) cation size [Tc(IV) = 78.5 pm ; Fe(III) = 69 or 78.5 pm], (2) metal-oxygen interatomic distance (Tc—O = 0.199 nm, Fe—O = 0.203 nm), (3) number of coordinating oxygen atoms (both 6-fold coordinated), and (4) the redox potential (Eh=ca. +20 mV at pH = 7) for a redox couple between Tc(VII)/Tc(IV) and Fe(III)/Fe(II). Magnetite, maghemite, and trevorite are iron oxide minerals and all belong to spinel mineral group. Laboratory testing shows that Tc can be removed from aqueous waste solutions by a process of Tc reduction from Tc(VII) to Tc(IV) followed by co-precipitation with iron oxide minerals during recrystallization of Fe(OH)2(s) used as an initial solid precursor. X-ray absorption near edge structure (XANES) spectroscopy confirmed that Tc was in the +4 oxidation state in final Tc-Fe minerals. The Tc-incorporated Fe minerals were also tested for Tc retention in glass melts at different temperatures between 600 – 1,000 oC in a furnace. After being cooled in air, the solid glass specimens collected at different temperatures were analyzed for Tc oxidation state using XANES and Tc retention using liquid scintillation counting (LSC). Even though Tc(IV) started to reoxidize at 600 oC, Tc retention in the final glass specimen prepared with Tc-incorporated Fe mineral even at high temperatures was at least two times higher than glass prepared with KTcO4 salt. Higher Tc retention in glass is considered to result from limited and delayed Tc volatilization process due to Fe mineral encapsulation for Tc. Therefore, the results showing the presence of Tc(IV) in the Fe mineral structure indicate strong possibility to enhance Tc retention in borosilicate glass as well as to reduce the remediation costs at the Hanford Site.

  10. Radioactive equilibrium: 99Mo/99mTc decay characteristics.

    PubMed

    Chechev, Valery P; Bé, Marie-Martine

    2014-05-01

    Within the Decay Data Evaluation Project, as an example of a radioactive equilibrium with isomer, the (99)Mo/(99m)Tc equilibrium mixture decay characteristics are examined. The results of a new decay data evaluation are presented for (99)Mo/(99m)Tc decay to nuclear levels in (99)Tc. These evaluated data have been obtained using information published up to 2013.

  11. PREFACE: 2013 Joint IMEKO (International Measurement Confederation) TC1-TC7-TC13 Symposium: Measurement Across Physical and Behavioural Sciences

    NASA Astrophysics Data System (ADS)

    Battista Rossi, Giovanni; Crenna, Francesco; Belotti, Vittorio

    2013-09-01

    The 2013 Joint IMEKO (International Measurement Confederation) TC1-C7-TC13 was organised by the University of Genova - DIME/MEC, Measurement Laboratory, Italy, on 4-6 September 2013. The work of this symposium is reported in this volume. The scope of the symposium includes the main topics covered by the above Technical Committees: TC1 Education and Training in Measurement and Instrumentation TC7 Measurement Science TC13 Measurements in Biology and Medicine This is in keeping with the tradition set by the previous events of this well established series. There has been a special focus on measurement across physical and behavioural sciences, with the aim of highlighting the interdisciplinary character of measurement science and of promoting constructive interactions with scientists in other disciplines. The discussion was introduced by keynote lectures on measurement challenges in psychophysics, psychometrics and quantum physics. The symposium was attended by experts working in these areas from 18 countries, including USA, Australia and Japan, and provided a useful forum for them to share and exchange their work and ideas. In total over sixty papers are included in the volume, organised according to the presentation sessions. Each paper was independently peer-reviewed by two reviewers from a distinguished international panel. The Symposium was held in Genova, which was the European Capital of Culture in 2004, and took place in Palazzo Ducale, an important historical building whose construction started in the 13th century, and that has been the house of the Duke of Genova from the 14th century. Genova, whose name comes from the Latin word 'Janua' (meaning 'door', as January is the door month of the year), has been regarded over the centuries as a door connecting Europe with the different countries and cultures of the Mediterranean basin and thus was an appropriate site for an international symposium involving different and new scientific visions and approaches to

  12. Synthesis of trevorite to capture Tc

    SciTech Connect

    Tsui, Colin

    2011-09-02

    Spinel containing technetium can be used to prevent Tc volatilization during vitrification of radioactive waste. Spinel dissolves in glass at elevated temperatures. This study focuses on the synthesis of spinel and the retention of rhenium, a nonradioactive surrogate for Tc in the crystals. To produce trevorite, a nickel-iron spinel (NiFe2O4), Fe and Ni nitrates were mixed with alkali nitrates along with Al(OH)3 and heated to 500 to 800°C. The trevorite content in samples (up to 40 mass%) was measured with x-ray diffraction. Viable samples were rerun with KReO4. Scanning electron microscopy-energy dispersive spectroscopy detected that Re became partly immobilized in spinel-forming crystals.

  13. Reactivity of Tc at the Groundwater-Surface Water Interface

    NASA Astrophysics Data System (ADS)

    Zachara, J. M.; Fredrickson, J.; McKinley, J.

    2014-12-01

    Technetium-99 (t1/2 =211,000y) is environmentally mobile as the pertechnetate oxyanion [99Tc(VII)O4-(aq)]. Tc(VII) may react to less soluble Tc(IV) at intermediate redox potentials (Eo = -0.36 V) through heterogeneous reduction with solid-phase biogenic reaction products. 99Tc is forecast to migrate through groundwater to the Columbia River at the U.S. DOE Hanford site in Washington State. Discharge to surface water will occur through a groundwater-surface water interaction zone with complex hydrogeology and biogeochemistry that is stimulated by the overlapping nutrient regimes of groundwater and surface water. The reactivity of pertechnetate in reduced sediments from this zone was investigated to determine effects of biogenic ferrous-Fe and sulfide-S on Tc(VII) reduction rate; and the resulting speciation, mineral association, and physical location of Tc(IV). 99Tc(VII) was reduced to near detection (<10-9 Mol/L) over periods of days to months. Tc(VII) reduction rate was first order in [Tc(VII)]aq and sediment mass, but correlations with specific biogenic reductant concentrations [(Fe(II), ferrous mono-sulfide] were not found. Tc(IV) was isolated to fine-grained aggregates (0.1 to 0.5 mm) of "mud", consisting of primary mineral material embedded within a phyllosilicate or clay matrix. EXAFS revealed that product Tc(IV) existed as combinations of a Tc(IV)O2-like phase ,Tc(IV)-Fe surface clusters, and/or TcSx. Ferrous mono-sulfide was implicated as a more selective reductant. Migration of Tc(VII) through the interaction zone will be controlled by water residence time and the density and spatial distribution of fine-grained aggregates that host reductive biogeochemical processes in otherwise coarse-textured, partially oxygenated sediments.

  14. Telecom 2-A (TC2A)

    NASA Technical Reports Server (NTRS)

    Dulac, J.; Latour, J.

    1991-01-01

    The DSN (Deep Space Network) mission support requirements for Telecom 2-A (TC2A) are summarized. The Telecom 2-A will provide high-speed data link applications, telephone, and television service between France and overseas territories. The mission objectives are outlined and the DSN support requirements are defined through the presentation of tables and narratives describing the spacecraft flight profile; DSN support coverage; frequency assignments; support parameters for telemetry, command and support systems; and tracking support responsibility.

  15. Epitaxial thick film high-Tc SQUIDs

    NASA Astrophysics Data System (ADS)

    Faley, M. I.; Mi, S. B.; Jia, C. L.; Poppe, U.; Urban, K.; Fagaly, R. L.

    2008-02-01

    Low-noise operation of superconducting quantum interference devices (SQUIDs) in magnetic fields requires high critical current and strong pinning of vortices in the superconducting electrodes and in the flux transformer. Crack-free epitaxial high-Tc dc-SQUID structures with a total thickness ?5 μm and a surface roughness determined by 30 nm high growth spirals were prepared with YBa2Cu3O7-x (YBCO) films on MgO substrates buffered by a SrTiO3/BaZrO3-bilayer. HRTEM demonstrated a high quality epitaxial growth of the films. The YBCO films and SQUID structures deposited on the buffered MgO substrates had a superconducting transition temperature Tc exceeding 91 K and critical current densities Jc > 3 MA/cm2 at 77 K up to a thickness ~5 μm. The application of thicker superconducting and insulator films helped us to increase the critical current and dynamic range of the multilayer high-Tc flux transformer and improve the insulation between the superconducting layers. An optimization of SQUID inductance allowed us to fabricate 8 mm SQUID magnetometers with SQUID voltage swings of ~60 μV and a field resolution of ~30 fT/√Hz at 77 K.

  16. Interdecadal variation of TC frequency in Japan

    NASA Astrophysics Data System (ADS)

    Choi, Ki-Seon; Cha, Yu-Mi; Kang, Sung-Dae; Kim, Hae-Dong

    2015-07-01

    This study analyzed the climate regime shift using statistical change-point analysis on the time-series tropical cyclone (TC) frequency that affected Japan in July to September. The result showed that there was a significant change in 1995, and since then, it showed a trend of rapidly decreasing frequency. To determine the reason for this, differences between 1995 to 2012 (9512) period and 1978 to 1994 (7894) period were analyzed. First, regarding TC genesis, TCs during the 9512 period showed a characteristic of genesis from the southeast quadrant of the tropical and subtropical western North Pacific and TCs during the 7894 period showed their genesis from the northwest quadrant. Regarding a TC track, TCs in the 7894 period had a strong trend of moving from the far east sea of the Philippines via the East China Sea to the mid-latitude region in East Asia while TCs in the 9512 period showed a trend of moving from the Philippines toward the southern part of China westward. Thus, TC intensity in the 7894 period, which can absorb sufficient energy from the sea as they moved a long distance over the sea, was stronger than that of 9512. Large-scale environments were analyzed to determine the cause of such difference in TC activity occurred between two periods. During the 9512 period, anomalous cold and dry anticyclones were developed strongly in the East Asia continent. As a result, Korea and Japan were affected by the anomalous northerlies thereby preventing TCs in this period from moving toward the mid-latitude region in East Asia. Instead, anomalous easterlies (anomalous trade wind) were developed in the tropical western Pacific so that a high passage frequency from the Philippines to the south China region along the anomalous steering flows was revealed. The characteristics of the anomalous cold and dry anticyclone developed in the East Asia continent were also confirmed by the analysis of air temperature, relative humidity, and sensible heat net flux showing that

  17. Pretreatment of Tc-Containing Waste and Its Effect on Tc-99 Leaching From Grouts

    SciTech Connect

    Aloy, Albert; Kovarskaya, Elena N.; Harbour, John R.; Langton, Christine A.; Holtzscheiter, E. William

    2007-07-01

    A salt solution (doped with Tc-99), that simulates the salt waste stream to be processed at the Saltstone Production Facility, was immobilized in grout waste forms with and without (1) ground granulated blast furnace slag and (2) pretreatment with iron salts. The degree of immobilization of Tc-99 was measured through monolithic and crushed grout leaching tests. Although Fe (+2) was shown to be effective in reducing Tc-99 to the +4 state, the strong reducing nature of the blast furnace slag present in the grout formulation dominated the reduction of Tc-99 in the cured grouts. An effective diffusion coefficient of 4.75 x 10{sup -12} (Leach Index of 11.4) was measured using the ANSI/ANS-16.1 protocol. The leaching results show that, even in the presence of a concentrated salt solution, blast furnace slag can effectively reduce pertechnetate to the immobile +4 oxidation state. The measured diffusivity was introduced into a flow and transport model (PORFLOW) to calculate the release of Tc-99 from a Saltstone Vault as a function of hydraulic conductivity of the matrix. (authors)

  18. PRETREATMENT OF TC CONTAINING WASTE AND ITS EFFECT ON 99 TC LEACHING FROM GROUTS

    SciTech Connect

    Harbour, J

    2006-12-11

    A salt solution (doped with Tc-99), that simulates the salt waste stream to be processed at the Saltstone Production Facility, was immobilized in grout waste forms with and without (1) ground granulated blast furnace slag and (2) pretreatment with iron salts. The degree of immobilization of Tc-99 was measured through monolithic and crushed grout leaching tests. Although Fe (+2) was shown to be effective in reducing Tc-99 to the +4 state, the strong reducing nature of the blast furnace slag present in the grout formulation dominated the reduction of Tc-99 in the cured grouts. An effective diffusion coefficient of 4.75 x 10{sup -12} (Leach Index of 11.4) was measured using the ANSI/ANS-16.1 protocol. The leaching results show that, even in the presence of a concentrated salt solution, blast furnace slag can effectively reduce pertechnetate to the immobile +4 oxidation state. The measured diffusivity was introduced into a flow and transport model (PORFLOW) to calculate the release of Tc-99 from a Saltstone Vault as a function of hydraulic conductivity of the matrix.

  19. Retention of 99mTc-DMSA(III) and 99mTc-nanocolloid in different syringes affects imaging quality.

    PubMed

    Bauwens, Matthias; Pooters, Ivo; van der Pol, Jochen; Mottaghy, Felix M; van Kroonenburgh, Marinus

    2014-04-01

    (99m)Tc-dimercaptosuccinic acid [DMSA(III)] and colloidal human serum albumin ((99m)Tc-nanocolloid) are widely used radiopharmaceuticals. Recently, in our institution we encountered image quality problems in DMSA scans after changing the brand of syringes we were using, which triggered us to look into the adsorption properties of syringes from different brands for (99m)Tc-DMSA(III) and (99m)Tc-nanocolloid. We also describe a clinical case in which adsorption of (99m)Tc-DMSA(III) caused inferior imaging quality. DMSA and nanocolloid were labeled with (99m)Tc following manufacturer guidelines. After synthesis, syringes with (99m)Tc-DMSA(III) and (99m)Tc-nanocolloid were stored for 15, 30, 60, and 120 min. We evaluated Luer Lock syringes manufactured by different brands such as Artsana, Henke-Sass-Wolf, B. Braun Medical N.V., CODAN Medizinische Geräte GmbH & Co KG, Becton Dickinson and Company, and Terumo Europe. Adsorption of (99m)Tc-DMSA(III) and (99m)Tc-nanocolloid was acceptably low for all syringes (<13%), except for two brands with (99m)Tc-DMSA(III) adsorption rates of 36 and 30%, respectively, and for one brand with a (99m)Tc-nanocolloid adsorption rate of 27%. Adsorption of (99m)Tc-DMSA(III) and (99m)Tc-nanocolloid reaches critical levels in syringes produced by two brands, potentially causing poor image quality--for example, in DMSA scans using pediatric radiopharmaceutical doses. It is advised to check the compatibility of any radiopharmaceutical with syringes as an integral part of the quality assurance program.

  20. High Tc superconducting materials and devices

    NASA Technical Reports Server (NTRS)

    Haertling, Gene H.

    1990-01-01

    The high Tc Y1Ba2Cu3O(7-x) ceramic materials, initially developed in 1987, are now being extensively investigated for a variety of engineering applications. The superconductor applications which are presently identified as of most interest to NASA-LaRC are low-noise, low thermal conductivity grounding links; large-area linear Meissner-effect bearings; and sensitive, low-noise sensors and leads. Devices designed for these applications require the development of a number of processing and fabrication technologies. Included among the technologies most specific to the present needs are tapecasting, melt texturing, magnetic field grain alignment, superconductor/polymer composite fabrication, thin film MOD (metal-organic decomposition) processing, screen printing of thick films, and photolithography of thin films. The overall objective of the program was to establish a high Tc superconductivity laboratory capability at NASA-LaRC and demonstrate this capability by fabricating superconducting 123 material via bulk and thin film processes. Specific objectives include: order equipment and set up laboratory; prepare 1 kg batches of 123 material via oxide raw material; construct tapecaster and tapecaster 123 material; fabricate 123 grounding link; fabricate 123 composite for Meissner linear bearing; develop 123 thin film processes (nitrates, acetates); establish Tc and Jc measurement capability; and set up a commercial use of space program in superconductivity at LaRC. In general, most of the objectives of the program were met. Finally, efforts to implement a commercial use of space program in superconductivity at LaRC were completed and at least two industrial companies have indicated their interest in participating.

  1. High Tc superconducting materials and devices

    NASA Astrophysics Data System (ADS)

    Haertling, Gene H.

    1990-09-01

    The high Tc Y1Ba2Cu3O(7-x) ceramic materials, initially developed in 1987, are now being extensively investigated for a variety of engineering applications. The superconductor applications which are presently identified as of most interest to NASA-LaRC are low-noise, low thermal conductivity grounding links; large-area linear Meissner-effect bearings; and sensitive, low-noise sensors and leads. Devices designed for these applications require the development of a number of processing and fabrication technologies. Included among the technologies most specific to the present needs are tapecasting, melt texturing, magnetic field grain alignment, superconductor/polymer composite fabrication, thin film MOD (metal-organic decomposition) processing, screen printing of thick films, and photolithography of thin films. The overall objective of the program was to establish a high Tc superconductivity laboratory capability at NASA-LaRC and demonstrate this capability by fabricating superconducting 123 material via bulk and thin film processes. Specific objectives include: order equipment and set up laboratory; prepare 1 kg batches of 123 material via oxide raw material; construct tapecaster and tapecaster 123 material; fabricate 123 grounding link; fabricate 123 composite for Meissner linear bearing; develop 123 thin film processes (nitrates, acetates); establish Tc and Jc measurement capability; and set up a commercial use of space program in superconductivity at LaRC. In general, most of the objectives of the program were met. Finally, efforts to implement a commercial use of space program in superconductivity at LaRC were completed and at least two industrial companies have indicated their interest in participating.

  2. High-Tc SQUID magnetocardiography imaging system.

    PubMed

    Yang, H C; Hung, S Y; Wu, C H; Chen, J C; Hsu, S J; Liao, S H; Horng, H E

    2004-11-30

    We set up a high-Tc SQUID system for magnetocardiography (MCG) in a moderately magnetically shielded room. The electronically balanced gradiometer consists of superconducting quantum interference device (SQUID) magnetometer. One reference SQUID was mounted above the sensing SQUID while the sensing SQUID is seated at the bottom of the cryostat. The baseline of the gradiometer is varied from 5 cm to 7 cm. The output of the MCG signal was filtered with the band pass filter (0.5 - 40 Hz) and the power-line filter. The MCG system was used to detect the magnetic signal of the human heart. Equivalent current sources were used to study the inverse problem.

  3. [Research of 99mTcO4- and 99mTcO2- in injectable solutions of 99mTc-HMDP by inverse phase HPTLC].

    PubMed

    Jacquot, Y; Zoubir, Br; Xicluna, A; Bidet, A-Cl

    2006-01-01

    Bone scintigraphy allows the diagnostic of many pathologies related to bone through the intravenous administration of a phosphonate bone marker complexed to 99 metastable technetium (99mTc). The instability of these injectable solutions on contact with air can lead to a mixture of pertechnetate VII (99mTcO4-) and technetium IV (99mTcO2-, xH2O), technetium IV being the only derivative to fix bone. A qualitative control of the purity of these solutions proved to be consequently important before administration. We report here the perfecting of a new chromatographic test based on reverse phase high performance thin layer chromatography (HPTLC). This test, simple, rapid and reproductive allows without ambiguity the detection of 99mTcO4-(VII) and 99mTcO2-(IV), xH2O in hydroxymethylene diphosphonate (HMDP) injectable solutions ready to use.

  4. Comparison of the tumor-seeking agent Tc-99m(V) dimercaptosuccinic acid and the renal imaging agent Tc-99m dimercaptosuccinic acid in humans

    SciTech Connect

    Ohta, H.; Ishii, M.; Yoshizumi, M.; Endo, K.; Sakahara, H.; Nakajima, T.; Yomoda, I.; Masuda, H.; Horiuchi, K.; Hata, N.

    1985-03-01

    Being aware of the ideal nuclear properties of Tc-99m, interest has been focused on the design of the (+5) oxidation state Tc-99m(V) dimercaptosuccinic acid (Tc(V)-DMSA) as a tumor-seeking agent. Tc-99m(V) DMSA holds a TcO4(3-) core and, like PO4(3-), has excellent characteristics for tumor uptake, but has a different distribution than the well-known renal scanning agent, Tc-99m DMSA. The differences in chemical behavior of Tc-99m(V) DMSA and Tc-99m DMSA are discussed. Three cases in which neoplasms were studied with Tc-99m(V) DMSA and Tc-99m DMSA are presented. Tc-99m DMSA and Tc-99m(V) DMSA, having a common ligand and tracer but, with the metal ion core in a different oxidation state, the uptake characteristics are altered markedly.

  5. sup 99m Tc renal tubular function agents: Current status

    SciTech Connect

    Eshima, D.; Fritzberg, A.R.; Taylor, A. Jr. )

    1990-01-01

    Orthoiodohippuric (OIH) acid labeled with 131I is a widely used renal radiopharmaceutical agent and has been the standard radiopharmaceutical agent for the measurement of effective renal plasma flow (EPRF). Limitations to the routine clinical use of 131I OIH are related to the suboptimal imaging properties of the 131I radionuclide and its relatively high radiation dose. 123I has been substituted for 131I; however, its high cost and short shelf-life have limited its widespread use. Recent work has centered on the development of a new 99mTc renal tubular function agent, which would use the optimal radionuclidic properties and availability of 99mTc and combine the clinical information provided by OIH. The search for a suitable 99mTc renal tubular function agent has focused on the diamide dithiolate (N2S2), the paraaminohippuric iminodiacetic acid (PAHIDA), and the triamide mercaptide (N3S) donor ligand systems. To date, the most promising 99mTc tubular function agent is the N3S complex: 99mTc mercaptoacetyltriglycine (99mTc MAG3). Studies in animal models in diuresis, dehydration, acid or base imbalance, ischemia, and renal artery stenosis demonstrate that 99mTc MAG3 behaves similarly to 131I OIH. A simple kit formulation is available that yields the 99mTc MAG3 complex in high radiochemical purity. Studies in normal subjects and patients indicate that 99mTc MAG3 is an excellent 99mTc renal tubular agent, but its plasma clearance is only 50% to 60% that of OIH. In an effort to develop an improved 99mTc renal tubular function agent, changes have been made in the core N3S donor ligand system, but to date no agent has been synthesized that is clinically superior to 99mTc MAG3. 61 references.

  6. Pressure and high-Tc superconductivity in sulfur hydrides

    PubMed Central

    Gor’kov, Lev P.; Kresin, Vladimir Z.

    2016-01-01

    The paper discusses fundamentals of record-TC superconductivity discovered under high pressure in sulfur hydride. The rapid increase of TC with pressure in the vicinity of Pcr ≈ 123GPa is interpreted as the fingerprint of a first-order structural transition. Based on the cubic symmetry of the high-TC phase, it is argued that the lower-TC phase has a different periodicity, possibly related to an instability with a commensurate structural vector. In addition to the acoustic branches, the phonon spectrum of H3S contains hydrogen modes with much higher frequencies. Because of the complex spectrum, usual methods of calculating TC are here inapplicable. A modified approach is formulated and shown to provide realistic values for TC and to determine the relative contributions of optical and acoustic branches. The isotope effect (change of TC upon Deuterium for Hydrogen substitution) originates from high frequency phonons and differs in the two phases. The decrease of TC following its maximum in the high-TC phase is a sign of intermixing with pairing at hole-like pockets which arise in the energy spectrum of the cubic phase at the structural transition. On-pockets pairing leads to the appearance of a second gap and is remarkable for its non-adiabatic regime: hydrogen mode frequencies are comparable to the Fermi energy. PMID:27167334

  7. High-Tc superconductors in the two-dimensional limit:

    PubMed

    Choy; Kwon; Park

    1998-06-05

    The free modulation of interlayer distance in a layered high-transition temperature (high-Tc) superconductor is of crucial importance not only for the study of the superconducting mechanism but also for the practical application of high-Tc superconducting materials. Two-dimensional (2D) superconductors were achieved by intercalating a long-chain organic compound into bismuth-based high-Tc cuprates. Although the intercalation of the organic chain increased the interlayer distance remarkably, to tens of angstroms, the superconducting transition temperature of the intercalate was nearly the same as that of the pristine material, suggesting the 2D nature of the high-Tc superconductivity.

  8. 99mTc-ciprofloxacin for diagnosis of bacterial infection

    NASA Astrophysics Data System (ADS)

    Aungurarat, A.; Ngamprayad, T.; Dangprasert, M.; Phumkem, S.; Jowanaridhi, B.

    2015-05-01

    Preparation of 99mTc-ciprofloxacin for diagnosis of bacterial infection was investigated by varying factors which affected this compound. The optimum conditions for preparation of 99mTc-ciprofloxacin and a lyophilized kit for Tc-99m labelling were studied. The results from biodistribution study showed that the percentages of the injected dose per gram tissues of infected area at 1 and 3 hours after injection were around 0.25-0.56. 99mTc-ciprofloxacin was found sterile, pyrogen-free and non-toxic. Radiochemical purity was greater than 90% with greater than 6 hours of stability.

  9. Imaging of irradiated liver with Tc-99m-sulfur colloid and Tc-99m-IDA

    SciTech Connect

    Gelfand, M.J.; Saha, S.; Aron, B.S.

    1981-09-01

    In three cases, irradiated regions of liver failed to concentrate Tc-99m-sulfur colloid. In two of these three, imaging with Tc-99m-acetanilide iminodiacetic acid (IDA) agents within five days showed near normal hepatic uptake of this hepatobiliary imaging agent. The hepatic parenchymal cells may be imaged with Tc-99m-IDA in some irradiated regions of liver, despite loss of reticuloendothelial cell function.

  10. Expanding the knowledge of the geographic distribution of Trypanosoma cruzi TcII and TcV/TcVI genotypes in the Brazilian Amazon.

    PubMed

    Lima, Valdirene Dos Santos; Xavier, Samanta Cristina das Chagas; Maldonado, Irene Fabíola Roman; Roque, André Luiz Rodrigues; Vicente, Ana Carolina Paulo; Jansen, Ana Maria

    2014-01-01

    Trypanosoma cruzi infection is a complex sylvatic enzooty involving a wide range of animal species. Six discrete typing units (DTUs) of T. cruzi, named TcI to TcVI, are currently recognized. One unanswered question concerning the epidemiology of T. cruzi is the distribution pattern of TcII and hybrid DTUs in nature, including their virtual absence in the Brazilian Amazon, the current endemic area of Chagas disease in Brazil. Herein, we characterized biological samples that were collected in previous epizootiological studies carried out in the Amazon Basin in Brazil. We performed T. cruzi genotyping using four polymorphic genes to identify T. cruzi DTUs: mini-exon, 1f8, histone 3 and gp72. This analysis was conducted in the following biological samples: (i) two T. cruzi isolates obtained by culturing of stools from the triatomine species Rhodnius picttipes and (ii) five serum samples from dogs in which trypomastigotes were observed during fresh blood examination. We report for the first time the presence of TcII and hybrid DTUs (TcV/TcVI) in the Amazon region in mixed infections with TcI. Furthermore, sequencing of the constitutive gene, gp72, demonstrated diversity in TcII even within the same forest fragment. These data show that TcII is distributed in the five main Brazilian biomes and is likely more prevalent than currently described. It is very probable that there is no biological or ecological barrier to the transmission and establishment of any DTU in any biome in Brazil.

  11. Expanding the Knowledge of the Geographic Distribution of Trypanosoma cruzi TcII and TcV/TcVI Genotypes in the Brazilian Amazon

    PubMed Central

    Lima, Valdirene dos Santos; Xavier, Samanta Cristina das Chagas; Maldonado, Irene Fabíola Roman; Roque, André Luiz Rodrigues; Vicente, Ana Carolina Paulo; Jansen, Ana Maria

    2014-01-01

    Trypanosoma cruzi infection is a complex sylvatic enzooty involving a wide range of animal species. Six discrete typing units (DTUs) of T. cruzi, named TcI to TcVI, are currently recognized. One unanswered question concerning the epidemiology of T. cruzi is the distribution pattern of TcII and hybrid DTUs in nature, including their virtual absence in the Brazilian Amazon, the current endemic area of Chagas disease in Brazil. Herein, we characterized biological samples that were collected in previous epizootiological studies carried out in the Amazon Basin in Brazil. We performed T. cruzi genotyping using four polymorphic genes to identify T. cruzi DTUs: mini-exon, 1f8, histone 3 and gp72. This analysis was conducted in the following biological samples: (i) two T. cruzi isolates obtained by culturing of stools from the triatomine species Rhodnius picttipes and (ii) five serum samples from dogs in which trypomastigotes were observed during fresh blood examination. We report for the first time the presence of TcII and hybrid DTUs (TcV/TcVI) in the Amazon region in mixed infections with TcI. Furthermore, sequencing of the constitutive gene, gp72, demonstrated diversity in TcII even within the same forest fragment. These data show that TcII is distributed in the five main Brazilian biomes and is likely more prevalent than currently described. It is very probable that there is no biological or ecological barrier to the transmission and establishment of any DTU in any biome in Brazil. PMID:25551227

  12. 99Tc Process Monitoring System In-Lab Performance Characterization

    SciTech Connect

    O'Hara, Matthew J.; Niver, Cynthia M.

    2014-01-01

    Executive Summary A 99Tc Process Monitoring (Tc-Mon) System has been designed and built for deployment at the recently constructed 200 West Pump & Treat (200W P&T) Plant in the 200 West Area ZP-1 Operable Unit of the Hanford Site. The plant is operated by CH2M Hill Plateau Remediation Company (CHPRC). The Tc-Mon system was created through collaboration between Pacific Northwest National Laboratory (PNNL) and Burge Environmental, Inc. The new system’s design has been optimized based on experience from an earlier field test (2011) of a prototype system at the 200W-ZP-1 Interim Pump & Treat Plant. A portion of the new 200W P&T Plant is dedicated to removal of 99Tc from contaminated groundwater in the 200 West Area. 99Tc, as the pertechnetate anion (99TcO4-), is remediated through delivery of water into two trains (Trains A and B) of three tandem extraction columns filled with Purolite A530E resin. The resin columns cannot be regenerated; therefore, once they have reached their maximum useful capacity, the columns must be disposed of as radioactive waste. The Tc-Mon system’s primary duty will be to periodically sample and analyze the effluents from each of the two primary extraction columns to determine 99Tc breakthrough. The Tc-Mon system will enable the CH2M Hill Plateau Remediation Company (CHPRC) to measure primary extraction column breakthrough on demand. In this manner, CHPRC will be able to utilize each extraction column to its maximum capacity. This will significantly reduce column disposal and replacement costs over the life of the plant. The Tc-Mon system was constructed by Burge Environmental, Inc. and was delivered to PNNL in June 2013 for setup and initial hardware and software performance testing in the 325 Building. By early July, PNNL had initiated an in-laboratory performance characterization study on the system. The objective was to fully calibrate the system and then evaluate the quality of the analytical outputs 1) against a series of clean

  13. High-Tc superconducting quantum interference device recordings of spontaneous brain activity: Towards high-Tc magnetoencephalography

    NASA Astrophysics Data System (ADS)

    Öisjöen, F.; Schneiderman, J. F.; Figueras, G. A.; Chukharkin, M. L.; Kalabukhov, A.; Hedström, A.; Elam, M.; Winkler, D.

    2012-03-01

    We have performed single- and two-channel high transition temperature (high-Tc) superconducting quantum interference device (SQUID) magnetoencephalography (MEG) recordings of spontaneous brain activity in two healthy human subjects. We demonstrate modulation of two well-known brain rhythms: the occipital alpha rhythm and the mu rhythm found in the motor cortex. We further show that despite higher noise-levels compared to their low-Tc counterparts, high-Tc SQUIDs can be used to detect and record physiologically relevant brain rhythms with comparable signal-to-noise ratios. These results indicate the utility of high-Tc technology in MEG recordings of a broader range of brain activity.

  14. The role of Tc-99m IDA hepatobiliary and Tc-99m colloid hepatic imaging in primary biliary cirrhosis

    SciTech Connect

    Aburano, T.; Yokoyama, K.; Shuke, N.; Kinuya, S.; Takayama, T.; Tonami, N.; Hisada, K. )

    1991-01-01

    To assess the presence of primary biliary cirrhosis, 15 patients at various histopathologic stages were studied by Tc-99m IDA hepatobiliary and/or Tc-99m colloid hepatic imaging. In the earlier stages (I and II), seven of eight patients (88%) showed uniform hepatic retention of Tc-99m IDA. Of seven patients in the same stage, however, four (57%) showed no abnormality on Tc-99m colliod imaging. In three of these four negative patients (75%), uniform hepatic retention of Tc-99m IDA was noted. In the later stages (III and IV), all seven patients showed decreased clearance with or without delayed tracer appearance in the intestine and prominent hepatic retention on Tc-99m IDA imaging; with Tc-99m colloid imaging there was enlargement of the spleen and increased activity in the spleen and bone marrow. Thus, Tc-99m IDA imaging is considered to be more useful in revealing this functional disorder at the earlier stage of primary biliary cirrhosis and in evaluating progression from an earlier to a later stage of disease. Tc-99m colloid imaging also effectively evaluated progression.

  15. Electron impact ionisation of encapsulated 99mTc@C 60 and 99mTc@C 70

    NASA Astrophysics Data System (ADS)

    Đustebek, J. B.; Đorđević, V. R.; Cvetićanin, J. M.; Veličković, S. R.; Veljković, M. V.; Nešković, O. M.; Rakočević, Z. L.; Bibić, N. M.

    2010-03-01

    The present study shows simultaneous surface ionisation and electron impact ionisation during the formation and investigation of endohedral fullerenes 99mTc@C 60 and 99mTc@C 70. The endohedral fullerenes were generated using a mass spectrometer with a triple rhenium filament as an ion source. The ionisation energies (IE) determined were: 8.52 ± 0.25 eV for 99mTc@C 60 and 9.57 ± 0.25 eV for 99mTc@ C 70.

  16. Pr77 and L1TcRz

    PubMed Central

    Sánchez-Luque, Francisco; López, Manuel C.; Macias, Francisco; Alonso, Carlos; Thomas, M. Carmen

    2012-01-01

    The sequence corresponding to the first 77 nucleotides of the L1Tc and NARTc non-LTR retrotransposons from Trypanosoma cruzi is an internal promoter (Pr77) that generates abundant, although poorly translatable, un-spliced transcripts. It has been recently described that L1TcRz, an HDV-like ribozyme, resides within the 5′-end of the RNA from the L1Tc and NARTc retrotransposons. Remarkably, the same first 77 nucleotides of L1Tc/NARTc elements comprise both the Pr77 internal promoter and the HDV-like L1TcRz. The L1TcRz cleaves on the 5′-side of the +1 nucleotide of the L1Tc element insuring that the promoter and the ribozyme functions travel with the transposon during retrotransposition. The ribozyme activity would prevent the mobilization of upstream sequences and insure the individuality of the L1Tc/NARTc copies transcribed from associated tandems. The Pr77/L1TcRz sequence is also found in other trypanosomatid’s non-LTR retrotransposons and degenerated retroposons. The possible conservation of the ribozyme activity in a widely degenerated retrotransposon, as the Leishmania SIDERs, could indicate that the presence of this element and the catalytic activity could play some favorable genetic regulation. The functional implications of the Pr77/L1TcRz dual system in the regulation of the L1Tc/NARTc retrotransposons and in the gene expression of trypanosomatids are also discussed in this paper. PMID:22754746

  17. High Tc composite silver/oxide superconductors

    NASA Technical Reports Server (NTRS)

    Curreri, P. A.; Peters, P. N.; Sisk, R. C.; Wu, M. K.; Huang, C. Y.

    1990-01-01

    Factors involved in the strong flux pinning effect of high-Tc YBa2Cu3O7/AgO (Y-123/AgO) composite and other REE-123/AgO composites were investigated. Samples of superconducting REE-123 and REE-123/AgO (where REE was Nd, Sm, Eu, Gd, Dy, Ho, Er, or Y) were prepared and used to obtain magnetic moments, critical field, and microstructure data. The optimum heat treatment conditions for the formation of strong flux-pinning REE-123/AgO composites were found to be different for different REE-123 compounds. It was found that the annealing temperature depends on the ionic size of the REE, with larger rare-earth ions requiring higher temperature. It was also found that strong flux-pinning REE-123/AgO composites form only in a narrow annealing temperature range.

  18. Raman Scattering in HIGH-Tc Superconductors

    NASA Astrophysics Data System (ADS)

    Thomsen, Christian; Cardona, Manuel

    The following sections are included: * INTRODUCTION * Theory * Light scattering by phonons * Electronic scattering * Instrumentation * VIBRATIONAL ANALYSIS AND LATTICE DYNAMICS * Optical Modes of RBa2Cu3O7-δ * Symmetry analysis of the ěc{k} = 0 modes * Lattice dynamical calculation for RBa2Cu3O7 and RBa2Cu3O6 * The Bismuth and Thallium Compounds * The Zurich Superconductors * EXPERIMENTAL RESULTS ON RBa2Cu3O7-δ * Raman Scattering by Phonons * Single crystals of YBa2Cu3O7-δ * Ceramic materials, impurity phases, and thin films * Oxygen deficiency * Isotope effect * Electronic scattering and the gap problem * Scattering by magnons * Bismuth and CuO2-Based Materials: Single-Crystal Spectra and Phonon Assignments * Thallium and CuO2 Based Materials * The Zurich Oxides * BRIEF COMPARISON WITH IR DATA * CONSEQUENCES CONCERNING THE MECHANISM OF HIGH-TC SUPERCONDUCTIVITY AND CONCLUSIONS * ACKNOWLEDGEMENTS * REFERENCES

  19. RILEM TC ISR Summer 2015 Activity Report

    SciTech Connect

    Le Pape, Yann

    2015-08-01

    With aging infrastructures, instances of Alkali Silica Reaction (ASR) and Delayed Ettringite Formation (DEF), broadly covered under the term Internal Swelling Reaction (ISR), are increasingly being detected. They have been observed in bridges, dams, and most recently in nuclear power plants. Concrete swelling may result in bridge partial failure, dams with structural cracks and misaligned turbine shafts, and locked slice gates. For nuclear reactors micro-cracks may cause increased gas permeability which will jeopardize the containment integrity and may decrease the residual structural resistance under accidental loading. This TC, which limits its activity to structures with known expansive concrete, seeks to address two complementary but fundamental questions: a) What is the kinetics of the reaction and b) How would it affect the integrity of the structure (serviceability and strength) and thus establish a science based prognostic to the structure owner.

  20. Real-Time Tropical Cyclone Prediction Using COAMPS-TC

    DTIC Science & Technology

    2011-01-01

    TC position estimates were directly assimilated with the EnKF system. Under-sampling issues in the data assimilation procedure associated with the...COAMPS-TC, a two-way interactive data assimilation procedure was implemented. In this algorithm, the innovations were defined using the highest

  1. Iron Oxide Waste Form for Stabilizing 99Tc

    SciTech Connect

    Um, Wooyong; Chang, Hyun-Shik; Icenhower, Jonathan P.; Lukens, Wayne W.; Serne, R. Jeffrey; Qafoku, Nikolla; Kukkadapu, Ravi K.; Westsik, Joseph H.

    2012-06-09

    Crystals of goethite were synthesized with reduced technetium [{sup 99}Tc(IV)] incorporated within the solid lattice. The presence of {sup 99}Tc(IV) as a substituting cation in the matrix and 'armoring' by an additional layer of precipitated goethite isolated the reduced {sup 99}Tc(IV) from oxidizing agents. These products were used to make monolithic pellets to quantify an effective diffusion coefficient for {sup 99}Tc from goethite waste form contacted with a synthetic Hanford IDF (integrated disposal facility) pore water solution (pH = 7.2, I = 0.05 M) at room temperature for up to 120 days in static reactors. XANES analysis of the goethite solids recovered post-run demonstrated that the {sup 99}Tc in the goethite crystals remains in the reduced {sup 99}Tc(IV) state. The slow release of pertechnetate concentration with time in the static experiments with the monolith followed a square root of time dependence, consistent with diffusion control for {sup 99}Tc release. An apparent diffusion coefficient of 6.15 x 10{sup -11} cm{sup 2}/s was calculated for the {sup 99}Tc-goethite pellet sample and the corresponding leaching index (LI) was 10.2. The results of this study indicate that technetium can be immobilized in a stable, low-cost Fe oxide matrix that is easy to fabricate and these findings can be useful in designing long-term solutions for nuclear waste disposal.

  2. Theoretical Modeling of 99 Tc NMR Chemical Shifts

    SciTech Connect

    Hall, Gabriel B.; Andersen, Amity; Washton, Nancy M.; Chatterjee, Sayandev; Levitskaia, Tatiana G.

    2016-09-06

    Technetium (Tc) displays a rich chemistry due to the wide range of oxidation states (from -I to +VII) and ability to form coordination compounds. Determination of Tc speciation in complex mixtures is a major challenge, and 99Tc NMR spec-troscopy is widely used to probe chemical environments of Tc in odd oxidation states. However interpretation of the 99Tc NMR data is hindered by the lack of reference compounds. DFT computations can help fill this gap, but to date few com-putational studies have focused on 99Tc NMR of compounds and complexes. This work systematically evaluates the inclu-sion small percentages of Hartree-Fock exchange correlation and relativistic effects in DFT computations to support in-terpretation of the 99Tc NMR spectra. Hybrid functionals are found to perform better than their pure GGA counterparts, and non-relativistic calculations have been found to generally show a lower mean absolute deviation from experiment. Overall non-relativistic PBE0 and B3PW91 calculations are found to most accurately predict 99Tc NMR chemical shifts.

  3. Iron oxide waste form for stabilizing 99Tc

    NASA Astrophysics Data System (ADS)

    Um, Wooyong; Chang, Hyunshik; Icenhower, Jonathan P.; Lukens, Wayne W.; Jeffrey Serne, R.; Qafoku, Nik; Kukkadapu, Ravi K.; Westsik, Joseph H.

    2012-10-01

    Crystals of goethite were synthesized with reduced technetium [99Tc(IV)] incorporated within the solid lattice. The presence of 99Tc(IV) as a substituting cation in the matrix and "armoring" by an additional layer of precipitated goethite isolated the reduced 99Tc(IV) from oxidizing agents. These products were used to make monolithic pellets to quantify an effective diffusion coefficient for 99Tc from goethite waste form contacted with a synthetic Hanford IDF (Integrated Disposal Facility) pore water solution (pH = 7.2 and I = 0.05 M) at room temperature for up to 120 days in static reactors. XANES analysis of the goethite solids recovered post-run demonstrated that the 99Tc in the goethite crystals remains in the reduced 99Tc(IV) state. The slow release of pertechnetate concentration with time in the static experiments with the monolith followed a square root of time dependence, consistent with diffusion control for 99Tc release. An apparent diffusion coefficient of 6.15 × 10-11 cm2/s was calculated for the 99Tc-goethite pellet sample and the corresponding leaching index (LI) was 10.2. The results of this study indicate that technetium can be immobilized in a stable, low-cost Fe oxide matrix that is easy to fabricate and these findings can be useful in designing long-term solutions for nuclear waste disposal.

  4. TC Research: State of the Art. Chapter 3.

    ERIC Educational Resources Information Center

    Acampora, Alfonso P., Ed.; Nebelkopf, Ethan, Ed.

    This document contains six papers from the ninth World Conference of Therapeutic Communities that highlight research on therapeutic communities (TC) and discuss how to apply research findings in practical ways. Papers include: (1) "TC Research: Overview & Implications" (George De Leon); (2) "Emerging Cross-Cultural TC…

  5. Impeding 99Tc(IV) mobility in novel waste forms

    DOE PAGES

    Lee, Mal-Soon; Um, Wooyong; Wang, Guohui; ...

    2016-06-30

    Technetium (99Tc) is a long-lived radioactive fission product whose mobility in the subsurface is largely governed by its oxidation state1. Immobilization of Tc in mineral substrates is crucial for radioactive waste management and environmental remediation. Tc(IV) incorporation in spinels2, 3 has been proposed as a novel method to increase Tc retention in glass waste forms. However, experiments with Tc-magnetite under high temperature and oxic conditions showed re-oxidation of Tc(IV) to volatile pertechnetate Tc(VII)O4-.4, 5 Here we address this problem with large-scale ab initio molecular dynamics simulations and propose that elevated temperatures, 1st row transition metal dopants can significantly enhance Tcmore » retention in the order Co > Zn > Ni. Experiments with doped spinels at T=700 ºC provided quantitative confirmation of increased Tc retention in the same order predicted by theory. This work highlights the power of modern state-of-the-art simulations to provide essential insights and generate bottom-up design criteria of complex oxide materials at elevated temperatures.« less

  6. Performance of TcI/TcVI/TcII Chagas-Flow ATE-IgG2a for universal and genotype-specific serodiagnosis of Trypanosoma cruzi infection.

    PubMed

    Alessio, Glaucia Diniz; de Araújo, Fernanda Fortes; Côrtes, Denise Fonseca; Sales Júnior, Policarpo Ademar; Lima, Daniela Cristina; Gomes, Matheus de Souza; do Amaral, Laurence Rodrigues; Xavier, Marcelo Antônio Pascoal; Teixeira-Carvalho, Andréa; Martins-Filho, Olindo Assis; de Lana, Marta

    2017-03-01

    Distinct Trypanosoma cruzi genotypes have been considered relevant for patient management and therapeutic response of Chagas disease. However, typing strategies for genotype-specific serodiagnosis of Chagas disease are still unavailable and requires standardization for practical application. In this study, an innovative TcI/TcVI/TcII Chagas Flow ATE-IgG2a technique was developed with applicability for universal and genotype-specific diagnosis of T. cruzi infection. For this purpose, the reactivity of serum samples (percentage of positive fluorescent parasites-PPFP) obtained from mice chronically infected with TcI/Colombiana, TcVI/CL or TcII/Y strain as well as non-infected controls were determined using amastigote-AMA, trypomastigote-TRYPO and epimastigote-EPI in parallel batches of TcI, TcVI and TcII target antigens. Data demonstrated that "α-TcII-TRYPO/1:500, cut-off/PPFP = 20%" presented an excellent performance for universal diagnosis of T. cruzi infection (AUC = 1.0, Se and Sp = 100%). The combined set of attributes "α-TcI-TRYPO/1:4,000, cut-off/PPFP = 50%", "α-TcII-AMA/1:1,000, cut-off/PPFP = 40%" and "α-TcVI-EPI/1:1,000, cut-off/PPFP = 45%" showed good performance to segregate infections with TcI/Colombiana, TcVI/CL or TcII/Y strain. Overall, hosts infected with TcI/Colombiana and TcII/Y strains displayed opposite patterns of reactivity with "α-TcI TRYPO" and "α-TcII AMA". Hosts infected with TcVI/CL strain showed a typical interweaved distribution pattern. The method presented a good performance for genotype-specific diagnosis, with global accuracy of 69% when the population/prototype scenario include TcI, TcVI and TcII infections and 94% when comprise only TcI and TcII infections. This study also proposes a receiver operating reactivity panel, providing a feasible tool to classify serum samples from hosts infected with distinct T. cruzi genotypes, supporting the potential of this method for universal and genotype-specific diagnosis of T. cruzi

  7. High -Tc superlight bipolarons in novel superconductors

    NASA Astrophysics Data System (ADS)

    Alexandrov, Sasha

    2003-03-01

    Over the last decade, several competing models of high-temperature superconductivity (HTSC) have been proposed, none of which have succeeded to explain high values of the superconducting critical temperature Tc without adjustable parameters. Most of the proposed models are based on the short-range electron-electron correlations or/and on a short-range electron-phonon interaction. However, in the cuprates the screening is poor due to the low carrier density, layered crystal structure, and high ionicity of the lattice. Here we develop further a model of HTSC, which explicitly takes into account the long-range origin of both types of interaction [1]. The long-range electron-phonon (Froehlich) interaction binds carriers into real space pairs-small bipolarons with surprisingly low mass but sufficient binding energy, while the long-range Coulomb repulsion keeps them from forming larger clusters. We analytically solve this multi-polaron "Froelich-Coulomb" model of oxides for a zigzag ladder and a perovskite layer [2]. The model numerically explains high Tc values in the cuprates without any fitting parameters. It describes other key features of the cuprates such as the isotope effect on the effective mass, pseudogap, the normal state diamagnetism, anomalous upper critical field, and spectral functions measured in tunnelling and photoemission. We argue that strong coupling of carriers with high-frequency phonons and low Fermi energies is the cause of high critical temperatures of novel superconductors. [1] A.S. Alexandrov, in Models and Phenomenology for Conventional and High-temperature Superconductivity (Course CXXXVI of the International School of Physics`Enrico Fermi'), eds. G. Iadonisi, J.R. Schrieffer and M.L. Chiofalo, (IOS Press, Amsterdam), p. 309 (1998). [2] A.S. Alexandrov and P.E. Kornilovitch, J. Phys.: Condens. Matter 14 (2002) 5337. * Mailing address: Department of Physics, Loughborough University, Loughborough LE11 3TU, United Kingdom; E-mail: a

  8. Impeding 99Tc(IV) mobility in novel waste forms

    NASA Astrophysics Data System (ADS)

    Lee, Mal-Soon; Um, Wooyong; Wang, Guohui; Kruger, Albert A.; Lukens, Wayne W.; Rousseau, Roger; Glezakou, Vassiliki-Alexandra

    2016-06-01

    Technetium (99Tc) is an abundant, long-lived radioactive fission product whose mobility in the subsurface is largely governed by its oxidation state. Tc immobilization is crucial for radioactive waste management and environmental remediation. Tc(IV) incorporation in spinels has been proposed as a novel method to increase Tc retention in glass waste forms during vitrification. However, experiments under high-temperature and oxic conditions show reoxidation of Tc(IV) to volatile pertechnetate, Tc(VII). Here we examine this problem with ab initio molecular dynamics simulations and propose that, at elevated temperatures, doping with first row transition metal can significantly enhance Tc retention in magnetite in the order Co>Zn>Ni. Experiments with doped spinels at 700 °C provide quantitative confirmation of the theoretical predictions in the same order. This work highlights the power of modern, state-of-the-art simulations to provide essential insights and generate theory-inspired design criteria of complex materials at elevated temperatures.

  9. Interactions of Tc(IV) with humic substances

    SciTech Connect

    Boggs, M. A.; Minton, Travis; Lomasney, Samuel; Islam, Mohammed; Dong, Wenming; Gu, Baohua; Wall, Nathalie

    2011-01-01

    To understand the key processes affecting 99Tc mobility in the subsurface and help with the remediation of contaminated sites, the binding constants of several humic substances (humic and fulvic acids) with Tc(IV) were determined, using a solvent extraction technique. The novelty of this paper lies in the determination of the binding constants of the complexes formed with the individual species TcO(OH)+ and TcO(OH)20. Binding constants were found to be 6.8 and between 3.9 and 4.3, for log 1, 1,1 and log 1,-2,1, respectively; these values were little modified by a change of ionic strength, in most cases, between 0.1 M to 1.0 M, nor were they by the nature and origin of the humic substances. Modeling calculations based on these show TcO(OH)-HA to be the predominant complex in a system containing 20 ppm HA and in the 4-6 pH range, while TcO(OH)20 and TcO(OH)2-HA are the major species, in the pH 6-8 range.

  10. Impeding 99Tc(IV) mobility in novel waste forms

    PubMed Central

    Lee, Mal-Soon; Um, Wooyong; Wang, Guohui; Kruger, Albert A.; Lukens, Wayne W.; Rousseau, Roger; Glezakou, Vassiliki-Alexandra

    2016-01-01

    Technetium (99Tc) is an abundant, long-lived radioactive fission product whose mobility in the subsurface is largely governed by its oxidation state. Tc immobilization is crucial for radioactive waste management and environmental remediation. Tc(IV) incorporation in spinels has been proposed as a novel method to increase Tc retention in glass waste forms during vitrification. However, experiments under high-temperature and oxic conditions show reoxidation of Tc(IV) to volatile pertechnetate, Tc(VII). Here we examine this problem with ab initio molecular dynamics simulations and propose that, at elevated temperatures, doping with first row transition metal can significantly enhance Tc retention in magnetite in the order Co>Zn>Ni. Experiments with doped spinels at 700 °C provide quantitative confirmation of the theoretical predictions in the same order. This work highlights the power of modern, state-of-the-art simulations to provide essential insights and generate theory-inspired design criteria of complex materials at elevated temperatures. PMID:27357121

  11. Thermodynamics of technetium related to nuclear waste disposal: Solubilities of Tc(IV) oxides and the electrode potential of the Tc(VII)/Tc(IV)--oxide couple

    SciTech Connect

    Meyer, R E; Arnold, W D; Case, F I; O'Kelley, G D

    1989-06-01

    Solubilities of Tc(IV) oxides have been determined in a number of solutions in the pH range 1 to 10. Technetium oxide was prepared by precipitation upon purified sand with a 30% excess of hydrazine and by electrodeposition. The oxide-covered sand was transferred to a small column, and the solutions to be studied were continuously cycled through the column. The electrodeposited oxide was formed on a platinum mesh electrode, and after careful rinsing, the solution to be studied was added to the electrolytic cell. The concentrations of total technetium and Tc(IV) species in the solutions were periodically determined by separating the oxidized and reduced technetium species using a solvent extraction procedure and counting the beta activity of the /sup 99/Tc with a liquid scintillation counter. In basic solutions, the concentrations of Tc(IV) species in equilibrium with the oxide were in the range of 10/sup /minus/8/ to 10/sup /minus/9/ mol/L and tended to increase slightly with pH. In acid solutions the concentrations were much higher and were consistent with literature data on the hydrolytic species of Tc(IV). Solubilities appeared to reach a minimum in the intermediate pH range, and they were generally a factor of three or four lower for oxides electrodeposited in basic solutions compared to those for oxides electrodeposited from acid solution. The oxides were hydrated, and assuming a formula of TcO/sub 2//center dot/nH/sub 2/O, the value of n was found to be 1.63 +- 0.28. These data can be used to estimate Tc(IV) solubilities for cases where solubility limits transport of technetium in reducing environments of high-level waste repositories. 22 refs., 7 figs., 9 tabs.

  12. Unconventional high-Tc superconductivity in fullerides.

    PubMed

    Takabayashi, Yasuhiro; Prassides, Kosmas

    2016-09-13

    A3C60 molecular superconductors share a common electronic phase diagram with unconventional high-temperature superconductors such as the cuprates: superconductivity emerges from an antiferromagnetic strongly correlated Mott-insulating state upon tuning a parameter such as pressure (bandwidth control) accompanied by a dome-shaped dependence of the critical temperature, Tc However, unlike atom-based superconductors, the parent state from which superconductivity emerges solely by changing an electronic parameter-the overlap between the outer wave functions of the constituent molecules-is controlled by the C60 (3-) molecular electronic structure via the on-molecule Jahn-Teller effect influence of molecular geometry and spin state. Destruction of the parent Mott-Jahn-Teller state through chemical or physical pressurization yields an unconventional Jahn-Teller metal, where quasi-localized and itinerant electron behaviours coexist. Localized features gradually disappear with lattice contraction and conventional Fermi liquid behaviour is recovered. The nature of the underlying (correlated versus weak-coupling Bardeen-Cooper-Schrieffer theory) s-wave superconducting states mirrors the unconventional/conventional metal dichotomy: the highest superconducting critical temperature occurs at the crossover between Jahn-Teller and Fermi liquid metal when the Jahn-Teller distortion melts.This article is part of the themed issue 'Fullerenes: past, present and future, celebrating the 30th anniversary of Buckminster Fullerene'.

  13. Research on high Tc superconducting compounds

    NASA Technical Reports Server (NTRS)

    Oliver, Frederick W. (Principal Investigator)

    1996-01-01

    Mossbauer research using the 21.54 kev resonance radiation of Eu-151 on the high temperature superconductors Bi(2)Ca(0.5)Eu(0.5)Sr(2)CU2O(x), and EuBa(2)CU(3)O(7-x) is performed. For the Bismuth compound the Mossbauer measurements gave a weak signal at room temperature but improved at lower temperatures. Experimental data indicated that europium is located at only one crystallographic site. Isomer shift measurements were .69 + 0.02 mm/s with respect to EuF(3). The linewidth at room temperature was found to be 2.54 mm/s. This value falls within the values observed by other researchers on Eu based 1,2,3 high-Tc compounds. Our results also show the Eu to be trivalent with no trace of divalent europium present. Superconducting europium based 1,2,3 compounds were prepared and measurements completed. Our results show the Eu to be trivalent with no trace of divalent europium present. These compounds had an average isomer shift of .73 mm/s +/- O.02 for all samples made. One of these was irradiated with 3.5 X 10(exp 16) neutrons and a comparison made of the Mossbauer parameters for the irradiated and non-irradiated samples. Experimental results showed no difference between linewidths but a measurable effect was seen for the isomer shift.

  14. Measurements of the rf surface resistance of high- Tc superconductors

    SciTech Connect

    Delayen, J.R.; Bohn, C.L.; Roche, C.T.

    1990-01-01

    An experimental program is being conducted to assess the applicability of high-{Tc} superconductors for use in high power rf and microwave devices. The program involves the measurement of the rf surface resistance of high-{Tc} samples at frequencies between 0.15 and 40 GHz and rf surface magnetic fields as high as 640 gauss. Polycrystalline samples were found to have surface resistances which increase monotonically with rf-field amplitude, saturating at high field at a few percent of the normal-state surface resistance just above {Tc}. 13 refs., 2 figs., 1 tab.

  15. Statistical inference for tumor growth inhibition T/C ratio.

    PubMed

    Wu, Jianrong

    2010-09-01

    The tumor growth inhibition T/C ratio is commonly used to quantify treatment effects in drug screening tumor xenograft experiments. The T/C ratio is converted to an antitumor activity rating using an arbitrary cutoff point and often without any formal statistical inference. Here, we applied a nonparametric bootstrap method and a small sample likelihood ratio statistic to make a statistical inference of the T/C ratio, including both hypothesis testing and a confidence interval estimate. Furthermore, sample size and power are also discussed for statistical design of tumor xenograft experiments. Tumor xenograft data from an actual experiment were analyzed to illustrate the application.

  16. Applicability of plasmid calibrant pTC1507 in quantification of TC1507 maize: an interlaboratory study.

    PubMed

    Meng, Yanan; Liu, Xin; Wang, Shu; Zhang, Dabing; Yang, Litao

    2012-01-11

    To enforce the labeling regulations of genetically modified organisms (GMOs), the application of DNA plasmids as calibrants is becoming essential for the practical quantification of GMOs. This study reports the construction of plasmid pTC1507 for a quantification assay of genetically modified (GM) maize TC1507 and the collaborative ring trial in international validation of its applicability as a plasmid calibrant. pTC1507 includes one event-specific sequence of TC1507 maize and one unique sequence of maize endogenous gene zSSIIb. A total of eight GMO detection laboratories worldwide were invited to join the validation process, and test results were returned from all eight participants. Statistical analysis of the returned results showed that real-time PCR assays using pTC1507 as calibrant in both GM event-specific and endogenous gene quantifications had high PCR efficiency (ranging from 0.80 to 1.15) and good linearity (ranging from 0.9921 to 0.9998). In a quantification assay of five blind samples, the bias between the test values and true values ranged from 2.6 to 24.9%. All results indicated that the developed pTC1507 plasmid is applicable for the quantitative analysis of TC1507 maize and can be used as a suitable substitute for dried powder certified reference materials (CRMs).

  17. Quasiparticle tunneling spectroscopy of high {Tc} cuprates

    SciTech Connect

    Zasadzinski, J.; Ozyuzer, L.; Yusof, Z.; Chen, J.; Gray, K.E.; Mogilevsky, R.; Hinks, D.G.; Cobb, J.L.; Markert, J.T.

    1996-04-01

    Superconductor-insulator-normal metal (SIN) and superconductor-insulator-superconductor (SIS) tunnel junctions provide important information on pairing state symmetry and mechanism. Measurements of such junctions on high {Tc} superconductors (HTS) are reported using mechanical point contacts, which generally display the optimum characteristics that can be obtained from HTS native-surface tunnel barriers. New tunneling data on the infinite-layer cuprate, Sr{sub 1{minus}x}Nd{sub x}CuO{sub 2} are reported which show a remarkable similarity to another electron-doped cuprate, Nd{sub 1.85}Ce{sub 0.85}CuO{sub 4}. In particular, there is a strong, asymmetric linear background conductance that is indicative of inelastic tunneling from a continuum of states. A discussion is given of the anomalous dip feature found in the tunneling and photoemission data on BSCCO 2212. It is shown that a similar feature is found in many cuprate junctions and that this dip scales with the gap energy over a wide range. New data on the single-layer, tetragonal cuprate, Tl{sub 2}Ba{sub 2}CuO{sub 6} (Tl2201) are presented and discussed in light of recent published results on the similar compound HgBa{sub 2}CuO{sub 4} (Hg1201). The HG1201 data display a low, flat sub-gap tunneling conductance which is consistent with a BCS density of states whereas the T12201 data display a cusp-like feature at zero bias which is more consistent with d{sub x}2-{sub y}2 symmetry.

  18. Production of medical 99 m Tc isotope via photonuclear reaction

    NASA Astrophysics Data System (ADS)

    Fujiwara, M.; Nakai, K.; Takahashi, N.; Hayakawa, T.; Shizuma, T.; Miyamoto, S.; Fan, G. T.; Takemoto, A.; Yamaguchi, M.; Nishimura, M.

    2017-01-01

    99 m Tc with a 6 hour half-life is one of the most important medical isotopes used for the Single-Photon Emission Computed Tomography (SPECT) inspection in hospitals of US, Canada, Europe and Japan. 99 m Tc isotopes are extracted by the milking method from parent 99Mo isotopes with a 66 hour half-life. The supply of 99Mo isotopes now encounters a serious crisis. Hospitals may not suitably receive 99Mo medical isotopes in near future, due to difficulties in production by research nuclear reactors. Many countries are now looking for alternative ways to generate 99Mo isotopes other than those with research reactors. We discuss a sustained availability of 99 m Tc isotopes via the nat Mo(γ, n) photonuclear reaction, and discuss to solve technical problems for extracting pure 99 m Tc isotopes from other output materials of photonuclear reactions.

  19. Getters for Tc and I Removal from Liquid Waste

    NASA Astrophysics Data System (ADS)

    Qafoku, N. P.; Asmussen, M.; Lawter, A.; Neeway, J.; Smith, G.

    2015-12-01

    A cementitious waste form, Cast Stone, is being evaluated as a possible supplemental waste form for the low activity waste (LAW) at the Hanford Site, which contains significant amounts of radioactive 99Tc and 129I, as part of the tank waste cleanup mission. To improve the retention of Tc and/or I in Cast Stone, materials with a high affinity for Tc and/or I, termed "getters," can be added to decrease the rate of contaminant release and diffusivity, and improve Cast Stone performance. A series of kinetic batch sorption experiments was performed to determine the effectiveness of the getter materials. Several Tc getters [blast furnace slag, Sn (II) apatite, SnCl2, nanoporous Sn phosphate, KMS-2 (a potassium-metal-sulfide), and Sn(II) hydroxyapatite] and I getters [layered Bi hydroxide, natural argentite mineral, synthetic argentite, Ag-impregnated carbon, and Ag-exchanged zeolite] were tested in different solution media, 18.2 MΩ DI H2O and a caustic LAW waste simulant containing 6.5 M Na or 7.8 M Na. The experiments were conducted at room temperature in the presence or absence of air. Results indicated that most Tc getters (with the exception of KMS-2) performed better in the DI H2O solution than in the 6.5 and 7.8 M Na LAW simulant. In addition, Tc sequestration may be affected by the presence of other redox sensitive elements that were present in the LAW simulant, such as Cr. The Tc getter materials have been examined through various solid-state characterization techniques such as XRD, SEM/EDS, XANES and EXAFS which provided evidence for plausible mechanisms of aqueous Tc removal. The results indicated that the Tc precipitates differ depending on the getter material and that Tc(VII) is reduced to Tc(IV) in most of the getters but to a differing extents. For the I getters, Ag-exchanged zeolite and synthetic argentite were the most effective ones. The other I getters showed limited effectiveness for sorbing I under the high ionic strength and caustic

  20. A search for technetium (Tc II) in barium stars

    NASA Technical Reports Server (NTRS)

    Little-Marenin, Irene R.; Little, Stephen J.

    1987-01-01

    The authors searched without success for the lines of Tc II at 2647.02, 2610.00 and 2543.24 A in IUE spectra of the barium stars HR 5058, Omicron Vir, and Zeta Cap. The lack of Tc II implies that the observed s-process enhancements were produced more than half a million years ago and supports the suggestion that the spectral peculiarities of barium stars are probably related to the binary nature of the stars.

  1. Detection of the Cracks using High-Tc SQUID

    NASA Astrophysics Data System (ADS)

    Fujii, Tatsuhiko; Hyun-Sung, Tae; Takamatsu, Tsuyoshi; Sakuta, Ken; Itozaki, Hideo

    Eddy current non-distractive evaluation (NDE) is very useful technique for detection of cracks. We use the high-Tc SQUID in this system. First, we respect the result of this measurement by the finite element method. We can detect of the signal from the hole by NDE system with high-Tc SQUID. This result is reasonable to compare with the result of simulation. Finaly, we can detect of the hidden defect under 5mm depth from the sample surface.

  2. MMTS, a new subfamily of Tc1-like transposons.

    PubMed

    Ahn, Sang Jung; Kim, Moo-Sang; Jang, Jae Ho; Lim, Sang Uk; Lee, Hyung Ho

    2008-10-31

    A novel Tc1-like transposable element has been identified as a new DNA transposon in the mud loach, Misgurnus mizolepis. The M. mizolepis Tc1-like transposon (MMTS) is comprised of inverted terminal repeats and a single gene that codes Tc1-like transposase. The deduced amino acid sequence of the transposase-encoding region of MMTS transposon contains motifs including DDE motif, which was previously recognized in other Tc1-like transposons. However, putative MMTS transposase has only 34-37% identity with well-known Tc1, PPTN, and S elements at the amino acid level. In dot-hybridization analysis used to measure the copy numbers of the MMTS transposon in genomes of the mud loach, it was shown that the MMTS transposon is present at about 3.36 x 104 copies per 2 x 109 bp, and accounts for approximately 0.027% of the mud loach genome. Here, we also describe novel MMTS-like transposons from the genomes of carp-like fishes, flatfish species, and cichlid fishes, which bear conserved inverted repeats flanking an apparently intact transposase gene. Additionally, BLAST searches and phylogenetic analysis indicated that MMTS-like transposons evolved uniquely in fishes, and comprise a new subfamily of Tc1-like transposons, with only modest similarity to Drosophila melanogaster (foldback element FB4, HB2, HB1), Xenopus laevis, Xenopus tropicalis, and Anopheles gambiae (Frisky).

  3. Separation of tc from Uranium and development of metallic Technetium waste forms

    NASA Astrophysics Data System (ADS)

    Mausolf, Edward John

    The isotope Technetium-99 (99Tc) is a major fission product of the nuclear industry. In the last decade, approximately 20 tons of 99Tc have been produced by the US nuclear industry. Due to its long half-life (t1/2 = 214,000 yr), beta radiotoxicity, and high mobility as pertechnetate [TcO4]-, Tc represents long-term concern to the biosphere. Various options have been considered to manage 99Tc. One of them is its separation from spent fuel, conversion to the metal and incorporation into a metallic waste form for long-term disposal. After dissolution of spent fuel in nitric acid and extraction of U and Tc in organic media, previously developed methods can be used to separate Tc from U, convert the separate Tc stream to the metal and reuse the uranium component of the fuel. A variety of metallic waste forms, ranging from pure Tc metal to ternary Tc alloys combined with stainless steel (SS) and Zr are proposed. The goal of this work was to examine three major questions: What is the optimal method to separate Tc from U? After separation, what is the most efficient method to convert the Tc stream to Tc metal? Finally, what is the corrosion behavior of Tc metal, Tc-SS alloys and Tc-Zr-SS alloys in 0.01M NaCl? The goal is to predict the long term behavior of Tc metallic waste in a hypothetical storage environment. In this work, three methods have been used to separate Tc from U: anionic exchange resin, liquid-liquid extraction and precipitation. Of the three methods studied, anionic exchange resins is the most selective. After separation of Tc from U, three different methods were studied to convert the Tc stream to the metal: thermal treatment under hydrogen atmosphere, electrochemical and chemical reduction of pertechnetate in aqueous media. The thermal treatment of the Tc stream under hydrogen atmosphere is the preferred method to produce Tc metal. After Tc metal is isolated, it will be incorporated into a metal host phase. Three different waste forms were produced for

  4. Poor Tc-99m dimercaptosuccinic acid uptake, re-evaluation with Tc-99m MAG3 scintigraphy in Lowe syndrome.

    PubMed

    Koca, Gokhan; Atilgan, Hasan Ikbal; Demirel, Koray; Diri, Akif; Korkmaz, Meliha

    2011-10-01

    Tc-99m dimercaptosuccinic acid (DMSA) is filtered through the glomeruli and reabsorbed by the proximal tubules as low molecular weight proteins. In Lowe syndrome this mechanism is impaired and so poor DMSA uptake is seen. Poor DMSA uptake was shown in very few studies, but none mentioned normal Tc-99m MAG3 uptake. In this case, the patient had poor DMSA uptake, normal MAG3 uptake and a neurogenic bladder in anterior to the left kidney that attenuates left kidney.

  5. Human immunodeficiency virus-1 infection protects against a Tc1-to-Tc2 shift in CD8(+) T cells.

    PubMed

    Gulzar, Naveed; Diker, Bilge; Balasubramanian, Sowmya; Jiang, Janina Q; Copeland, Karen F T

    2011-11-01

    Despite the reports of dysfunction of the lytic abilities of CD8(+) T cells during human immunodeficiency virus-1 (HIV-1) disease progression, the effects of infection on the noncytolytic functions of CD8(+) T cells have not been well characterized to date. We examined the effect of HIV-1 infection on the cytokine and chemokine responses of peripheral blood-derived CD8(+) T cells in an in vitro system. Activation of HIV-1-infected CD8(+) T cells with phytohemagglutinin resulted in a 4- to 8-fold increase in the production of macrophage inflammatory protein (MIP)-1α, MIP-1β, regulated on activation normal T-cell expressed and secreted, and interleukin (IL)-16. Treatment of activated HIV-1-infected CD8(+) T cells with anti-CD3 monoclonal (M) antibody (Ab) and IL-15 induced strong production of interferon-γ (IFN-γ). Treatment of cells with anti-IL-12 MAb and IL-4 to induce a Tc1-to-Tc2 shift resulted in no change in viral production levels or IFN-γ production within the HIV-1-infected CD8(+) T cell population. Initiation of a Tc2-to-Tc1 shift resulted in a 6-fold increase in HIV-1 replication and 2- to 3-fold higher levels of IFN-γ, demonstrating that infection can protect against a Tc1-to-Tc2 shift in CD8(+) T cells.

  6. Power Systems Development Facility Gasification Test Campaign TC25

    SciTech Connect

    Southern Company Services

    2008-12-01

    In support of technology development to utilize coal for efficient, affordable, and environmentally clean power generation, the Power Systems Development Facility (PSDF), located in Wilsonville, Alabama, routinely demonstrates gasification technologies using various types of coals. The PSDF is an engineering scale demonstration of key features of advanced coal-fired power systems, including a KBR Transport Gasifier, a hot gas particulate control device, advanced syngas cleanup systems, and high-pressure solids handling systems. This report summarizes the results of TC25, the second test campaign using a high moisture lignite coal from the Red Hills mine in Mississippi as the feedstock in the modified Transport Gasifier configuration. TC25 was conducted from July 4, 2008, through August 12, 2008. During TC25, the PSDF gasification process operated for 742 hours in air-blown gasification mode. Operation with the Mississippi lignite was significantly improved in TC25 compared to the previous test (TC22) with this fuel due to the addition of a fluid bed coal dryer. The new dryer was installed to dry coals with very high moisture contents for reliable coal feeding. The TC25 test campaign demonstrated steady operation with high carbon conversion and optimized performance of the coal handling and gasifier systems. Operation during TC25 provided the opportunity for further testing of instrumentation enhancements, hot gas filter materials, and advanced syngas cleanup technologies. The PSDF site was also made available for testing of the National Energy Technology Laboratory's fuel cell module and Media Process Technology's hydrogen selective membrane with syngas from the Transport Gasifier.

  7. Power Systems Development Facility Gasification Test Run TC07

    SciTech Connect

    Southern Company Services

    2002-04-05

    This report discusses Test Campaign TC07 of the Kellogg Brown & Root, Inc. (KBR) Transport Reactor train with a Siemens Westinghouse Power Corporation (Siemens Westinghouse) particle filter system at the Power Systems Development Facility (PSDF) located in Wilsonville, Alabama. The Transport Reactor is an advanced circulating fluidized-bed reactor designed to operate as either a combustor or a gasifier using a particulate control device (PCD). The Transport Reactor was operated as a pressurized gasifier during TC07. Prior to TC07, the Transport Reactor was modified to allow operations as an oxygen-blown gasifier. Test Run TC07 was started on December 11, 2001, and the sand circulation tests (TC07A) were completed on December 14, 2001. The coal-feed tests (TC07B-D) were started on January 17, 2002 and completed on April 5, 2002. Due to operational difficulties with the reactor, the unit was taken offline several times. The reactor temperature was varied between 1,700 and 1,780 F at pressures from 200 to 240 psig. In TC07, 679 hours of solid circulation and 442 hours of coal feed, 398 hours with PRB coal and 44 hours with coal from the Calumet mine, and 33 hours of coke breeze feed were attained. Reactor operations were problematic due to instrumentation problems in the LMZ resulting in much higher than desired operating temperatures in the reactor. Both reactor and PCD operations were stable and the modifications to the lower part of the gasifier performed well while testing the gasifier with PRB coal feed.

  8. The Phosphatidylinositol 3-kinase Class III Complex Containing TcVps15 and TcVps34 Participates in Autophagy in Trypanosoma cruzi.

    PubMed

    Schoijet, Alejandra C; Sternlieb, Tamara; Alonso, Guillermo D

    2016-09-07

    Autophagy is a degradative process by which eukaryotic cells digest their own components to provide aminoacids that may function as energy source under nutritional stress conditions. There is experimental evidence for autophagy in parasitic protists belonging to the family Trypanosomatidae. However, few proteins implicated in this process have been characterized so far in these parasites. Moreover, it has been shown that autophagy is involved in Trypanosoma cruzi differentiation and thus might have a role in pathogenicity. Here, we report the cloning and biochemical characterization of TcVps15. In addition, we demonstrate that TcVps15 interact with the PI3K TcVps34 and that both proteins associate with cellular membranes. Under nutritional stress conditions, TcVps15 and TcVps34 modify their subcellular distribution showing a partial co-localization in autophagosomes with TcAtg8.1 and using an active site TcVps15-mutated version (TcVps15-K219D-HA) we demonstrated that this relocalization depends on the TcVps15 catalytic activity. Overexpression of TcVps15-HA and TcVps15-K219D-HA also leads to increased accumulation of monodansylcadaverine (MDC) in autophagic vacuoles under nutritional stress conditions compared to wild-type cells. In addition, the MDC-specific activity shows to be significantly higher in TcVps15-HA overexpressing cells when compared with TcVps15-K219D-HA. Our results reveal for the first time a role of TcVps15 as a key regulator of TcVps34 enzymatic activity and implicate the TcVps15-Vps34 complex in autophagy in T. cruzi, exposing a new key pathway to explore novel chemotherapeutic targets.

  9. Development of Tc-99m Imaging Agents for Abeta Plaques

    SciTech Connect

    Zhi-Ping, Zhuang; Mei-Ping Kung; Catherihne Hou; Hank F. Kung

    2008-09-26

    Development of SPECT imaging agents based on Tc-99m targeting Aβ plaques is useful for diagnosis of Alzheimer’s disease (AD). A stilbene derivative, [11C]SB-13, showing promise in detecting senile plaques present in AD patients has been reported previously1,2. Based on the 4’-amino-stilbene core structure we have added substituted groups through which a chelating group, N2S2, was conjugated. We report herein a series of Tc-99m labeled stilbene derivative conjugated with a TcO[N2S2] core. The syntheses of stilbenes containing a N2S2 chelating ligand are achieved by a scheme shown. Lipophilic 99mTc stilbene complexes were successfully prepared and purified through HPLC. Preliminary results of in vitro labeling of brain sections from transgenic mice showed very promising plaque labeling. These 99mTc stilbene derivatives are warranted for further evaluations as potential imaging agents targeting amyloid plaques.

  10. Iron phosphate glass for immobilization of 99Tc

    SciTech Connect

    Xu, Kai; Hrma, Pavel R.; Um, Wooyong; Heo, Jong

    2013-06-15

    Technetium-99 (99Tc) can bring serious environmental threats because of its long half-life (t1/2 = ~2.1 x 105 years), high fission yield (~6%), and high solubility and mobility in the ground water. The high volatility makes it difficult to immobilize 99Tc in continuous melters vitrifying 99Tc-containing nuclear wastes in borosilicate glasses. This work explores a possibility of incorporating a high concentration of 99Tc, surrogated by the non-radioactive Re, in an iron phosphate glass by melting mixtures of iron phosphate glass frits with 1.5-6 mass% KReO4 at ~1000 C. The retention of Re achieved was ~1.1 mass%. The normalized Re release by the 7-day Product Consistency Test was <10*2 g/m2. Surprisingly, the Re escaped from the melt within a short time of heating, especially when the temperature was increased. Therefore, 99Tc volatilization would still be a challenging task for its immobilization in iron phosphate glasses.

  11. Synthesis and evaluation of 99mTc/99Tc-MAG3-biotin conjugates for antibody pretargeting strategies.

    PubMed

    van Gog, F B; Visser, G W; Gowrising, R W; Snow, G B; van Dongen, G A

    1998-10-01

    Four 99mTc-MAG3-biotin conjugates were synthesized to determine their potential use in antibody pretargeting strategies for radioimmunoscintigraphy (RIS). To use these 99mTc-MAG3-biotin conjugates as model compounds for 186Re-MAG3-biotin conjugates for radioimmunotherapy (RIT), nanomolar amounts of 99Tc were added as carrier to 99mTc. The biotin derivatives used for the preparation of the conjugates-biocytin, biotin hydrazide, biotinyl-piperazine, and biotinyl-diaminosuccinic acid-differed at the site that is regarded to be susceptible to hydrolysis by biotinidase present in human plasma. All four conjugates were produced with high radiochemical purity, were stable in PBS, and demonstrated full binding capacity to streptavidin. The 99mTc/99Tc-MAG3-labeled biotinyl-piperazine and biotinyl-diaminosuccinic acid conjugates were stable in mouse as well as human plasma, whereas the corresponding biocytin and biotin hydrazide conjugates were rapidly degraded. The biodistribution in nude mice at 30 min after injection was similar for all conjugates, and a rapid blood clearance and high intestinal excretion were both observed. It is concluded that the metabolic routing of a conjugate containing biotin and MAG3 is dominated by these two moieties. For this reason, MAG3-biotin conjugates do not seem suited for pretargeted RIT, for which quantitative and fast renal excretion is a prerequisite to minimize radiation toxicity. However, in a pretargeted RIS approach the 99mTc-MAG3-biotin conjugates might have potential.

  12. Effects of non-magnetic doping on high- Tc cuprates

    NASA Astrophysics Data System (ADS)

    Ming-wen, Xiao; Zheng-zhong, Li; Da-ning, Shi

    1992-11-01

    The Anderson lattice model (ALM) is adopted to study the substitution effects of non-magnetic impurities at Cu-sites on the properties of high- Tc superconductors by the slave-boson technique. We found that they can weaken the effective strength of Cu O hybridization and lower the characteristic temperature Tk of the normal state. The ability of these effects to depress superconductivity is proved to be important and not negligible. Non-magnetic impurities turn out to be pair-breaking and responsible for the quick decreasing of Tc because of the energy dependence of the superconducting order parameter in ALM. Particularly, the linear relationship between Tc and doping concentration in the dilute case is obtained analytically, which is in good agreement with experiment.

  13. Bec Model of HIGH-Tc Superconductivity in Layered Cuprates

    NASA Astrophysics Data System (ADS)

    Lomnitz, M.; Villarreal, C.; de Llano, M.

    2013-11-01

    High-Tc superconductivity in layered cuprates is described in a BCS-BEC formalism with linearly-dispersive s- and d-wave Cooper pairs moving in quasi-2D finite-width layers around the CuO2 planes. This yields a closed formula for Tc involving the layer width, the Debye frequency, the pairing energy and the in-plane penetration depth. The new formula has no free parameters and reasonably reproduces empirical values of superconducting Tcs for 11 different layered superconductors over a wide doping regime including YBCO itself as well as other compounds like LSCO, BSCCO and TBCCO. In agreement with the London formalism, the formula also yields a fair description of the Tc dependence of the lower critical magnetic field in highly underdoped YBCO.

  14. Radionuclide imaging of myocardial infarction using Tc-99m TBI

    SciTech Connect

    Holman, B.L.; Campbell, S.; Kirshenbaum, J.M.; Lister-James, J.; Jones, A.G.; Davison, A.; Antman, E.

    1985-05-01

    The cationic complex Tc-99m t-butylisonitrile (TBI) concentrates in the myocardial tissue of several animal species. Its myocardial distribution is proportional to blood flow both in zones of ischemia and in normal myocardium at rest. Planar, tomographic, and gated myocardial images have been obtained using Tc-99m TBI in the human. The authors investigated the potential application of Tc-99m TBI imaging to detect and localize myocardial infarction. Four subjects without clinical evidence of cardiovascular disease and five patients with ECG evidence of previous myocardial infarction were studied. Tc-99m TBI (10mCi) was injected intravenously with the patient in a resting state with planar imaging in the anterior, 30 and 70 degree LAO projections beginning one hr after injection. The distribution of the tracer was homogeneous throughout the left ventricular wall in the normal subjects. Regional perfusion defects were present in 4/5 of the patients with myocardial infarction. Location of the defects corresponded to the location of the infarct using ECG criteria (2 inferoposterior and 2 anterior). The patient in whom the Tc-99m TBI image appeared normal had sustained a subendocardial myocardial infarct which could not be localized by ECG; the other 4 pts had transmural infarcts. Anterior and 30 degree LAO images were of excellent quality in all cases; there was overlap of the liver on the inferior wall of the left ventricle on the 70 degree LAO views. The authors conclude that accurate perfusion imaging may be possible using Tc-99m TBI in patients with transmural myocardial infarction.

  15. How to optimize high-Tc superconductive cuprates

    NASA Astrophysics Data System (ADS)

    Raveau, B.; Michel, C.; Hervieu, M.; Groult, D.; Maignan, A.; Provost, J.

    1992-06-01

    Several examples are used here to illustrate the way that modifying the structure of high-Tc superconductive cuprates (HTSCs) allows their superconducting properties to be significantly improved. It is shown that energetic heavy ions can be used as projectiles to modify and tailor superconducting properties. In particular, the creation of columnar defects with dimensions of Xi(ab) or more can act as efficient pinning centers for flux lines and can be used to extend the operating field range of HTSCs to substantially higher fields near Tc's. The crucial role of radiation-induced defects in controlling the magnetic hysteresis shape and therefore the critical current density is demonstrated.

  16. High Tc superconducting bolometric and nonbolometric infrared (IR) detectors

    NASA Technical Reports Server (NTRS)

    Lakeou, Samuel

    1994-01-01

    The original workplan for the first year of the project includes the following: establishment of a pilot superconductivity application laboratory at UDC to support the research component of the project; research on the source of electrical noise in High Tc superconducting films in order to optimize the film microstructure and lower the NEP; and lay the foundation of an academic support for exposing UDC students to the theory and application of High Tc superconductivity. Attached to this status report are abstracts and the course description for Introduction to Applications of Superconductivity.

  17. Rugged Low-Resistance Contacts To High-Tc Superconductors

    NASA Technical Reports Server (NTRS)

    Caton, Randall; Selim, Raouf; Byvik, Charles E.; Buoncristiani, A. Martin

    1992-01-01

    Newly developed technique involving use of gold makes possible to fabricate low-resistance contacts with rugged connections to high-Tc superconductors. Gold diffused into specimen of superconducting material by melting gold beads onto surface of specimen, making strong mechanical contacts. Shear strength of gold bead contacts greater than epoxy or silver paste. Practical use in high-current-carrying applications of new high-Tc materials, including superconducting magnets, long-wavelength sensors, electrical ground planes at low temperatures, and efficient transmission of power.

  18. An Economical Magnetocardiogram System Based on High-Tc SQUIDs

    NASA Astrophysics Data System (ADS)

    Li, Zhuo; Zhu, Xue-Min; Zhang, Li-Hua; Huang, Xu-Guang; Ren, Yu-Feng; Chen, Geng-Hua; Yang, Qian-Sheng; Feng, Ji

    2006-08-01

    An economical magnetocardiogram (MCG) system is built in our laboratory. It mainly consists of a MCG data acquisition stage equipped with two high-Tc superconducting quantum interference device (SQUID) magnetometers, a data processing stage with digital filtering and a one-layer μ-metal magnetically shielded room in conjunction with a high-Tc SQUID based active compensation. Experimental results show that a noise level of pico-tesla in MCG profiles, which is necessary for clinical applications, may be achieved with the system. Moreover, stable and convenient operations of the system are demonstrated with simulating MCG measurements.

  19. Comparative evaluation of Tc-99m cystine and Tc-99m MAG3 in normals and patients with renal functional impairment.

    PubMed

    Misra, Mridula; Pradhan, Prasanta K; De, Kakali; Chandra, Susmita; Das, Birendra K

    2009-03-01

    Tc-99m cystine has been proved to be a good renal agent in animals for morphologic as well as the functional status of the kidney. In this study, we compared Tc-99m cystine with Tc-99m mercaptoacetyltriglycine, which is used for evaluation of renal function in normal patients, and those with various degrees of renal functional impairment. The clearance values and static images are compared with Tc-99m mercaptoacetyltriglycine. The results show that Tc-99m cystine has good radiopharmaceutical characteristics suitable for evaluation of both renal function as well as morphology.

  20. Tc Reductant Chemistry and Crucible Melting Studies with Simulated Hanford Low-Activity Waste

    SciTech Connect

    Kim, Dong-Sang; Soderquist, Chuck Z.; Icenhower, Jonathan P.; McGrail, B PETER.; Scheele, Randall D.; McNamara, Bruce K.; Bagaasen, Larry M.; Schweiger, Michael J.; Crum, Jarrod V.; Yeager, John D.; Matyas, Josef; Darnell, Lori P.; Schaef, Herbert T.; Owen, Antionette T.; Kozelisky, Anne E.; Snow, Lanee A.; Steele, Marilyn J.

    2005-03-30

    The FY 2003 risk assessment (RA) of bulk vitrification (BV) waste packages used 0.3 wt% of the technetium (Tc) inventory as a leachable salt and found it sufficient to create a significant peak in the groundwater concentration in a 100-meter down-gradient well. Although this peak met regulatory limits, considering uncertainty in the actual Tc salt fraction, peak concentrations could exceed the maximum concentration limit (MCL) under some scenarios so reducing the leachable salt inventory is desirable. The main objective of this study was to reduce the mobile Tc species available within a BV disposal package by reducing the oxidation state of the Tc in the waste feed and/or during melting because Tc in its reduced form of Tc(IV) has a much lower volatility than Tc(VII). Reduced Tc volatility has a secondary benefit of increasing the Tc retention in glass.

  1. Tc-99 Adsorption on Selected Activated Carbons - Batch Testing Results

    SciTech Connect

    Mattigod, Shas V.; Wellman, Dawn M.; Golovich, Elizabeth C.; Cordova, Elsa A.; Smith, Ronald M.

    2010-12-01

    CH2M HILL Plateau Remediation Company (CHPRC) is currently developing a 200-West Area groundwater pump-and-treat system as the remedial action selected under the Comprehensive Environmental Response, Compensation, and Liability Act Record of Decision for Operable Unit (OU) 200-ZP-1. This report documents the results of treatability tests Pacific Northwest National Laboratory researchers conducted to quantify the ability of selected activated carbon products (or carbons) to adsorb technetium-99 (Tc-99) from 200-West Area groundwater. The Tc-99 adsorption performance of seven activated carbons (J177601 Calgon Fitrasorb 400, J177606 Siemens AC1230AWC, J177609 Carbon Resources CR-1240-AW, J177611 General Carbon GC20X50, J177612 Norit GAC830, J177613 Norit GAC830, and J177617 Nucon LW1230) were evaluated using water from well 299-W19-36. Four of the best performing carbons (J177606 Siemens AC1230AWC, J177609 Carbon Resources CR-1240-AW, J177611 General Carbon GC20X50, and J177613 Norit GAC830) were selected for batch isotherm testing. The batch isotherm tests on four of the selected carbons indicated that under lower nitrate concentration conditions (382 mg/L), Kd values ranged from 6,000 to 20,000 mL/g. In comparison. Under higher nitrate (750 mg/L) conditions, there was a measureable decrease in Tc-99 adsorption with Kd values ranging from 3,000 to 7,000 mL/g. The adsorption data fit both the Langmuir and the Freundlich equations. Supplemental tests were conducted using the two carbons that demonstrated the highest adsorption capacity to resolve the issue of the best fit isotherm. These tests indicated that Langmuir isotherms provided the best fit for Tc-99 adsorption under low nitrate concentration conditions. At the design basis concentration of Tc 0.865 µg/L(14,700 pCi/L), the predicted Kd values from using Langmuir isotherm constants were 5,980 mL/g and 6,870 mL/g for for the two carbons. These Kd values did not meet the target Kd value of 9,000 mL/g. Tests

  2. Standards and biomedical terminologies: the CEN TC 251 and ISO TC 215 categorial structures. A step towards increased interoperability.

    PubMed

    Rodrigues, Jean M; Kumar, Anand; Bousquet, Cédric; Trombert, Béatrice

    2008-01-01

    Among different biomedical terminologies standardisation strategies the European Standard Body CEN TC 251 followed by the ISO TC 215 have stated that it was not possible to convince the different European or international member states using different national languages to agree on a reference clinical terminology or to standardise a detailed language independent biomedical ontology. Since 1990, they have developed an approach named categorial structure as a step standardising only the terminologies model structure. The methodology and the review of the different existing categorial structures are presented as a step towards increased interoperability between biomedical terminologies thanks to conformity to a minimum set of ontological requirements.

  3. Effects of FlAsH/Tetracysteine (TC) tag on PrP proteolysis and PrPres formation by TC-scanning

    PubMed Central

    Taguchi, Yuzuru; Hohsfield, Lindsay A.; Hollister, Jason R.

    2014-01-01

    The FlAsH/tetracysteine (FlAsH/TC) tag is a powerful tool for fluorescent labeling of proteins. However, even small tags such as FlAsH/TC could alter the behavior of the tagged proteins, especially if the insertion occurs at internal sites. Defining the influence of FlAsH/TC on nearby protein-protein interactions might aid in selecting appropriate positions for internal TC insertions and allow the exploitation of serial FlAsH/TC insertions (TC-scanning) as a probe to characterize sites of protein-protein interaction. To explore this application in the context of substrate-protease interactions, we analyzed the effect of FlAsH/TC insertions on proteolysis of cellular prion protein (PrPsen) in in vitro reactions and generation of the C1 metabolic fragment of PrPsen in live neuroblastoma cells. The influence of FlAsH/TC insertion was evaluated by TC-scanning across the cleavage sites of each protease. The results showed that FlAsH/TC inhibited protease cleavage only within limited ranges of the cleavage sites that varied from about 1 to 6 residues-wide depending on the protease, providing an estimate of the PrP residues interacting with each protease. TC-scanning was also used to probe a different type of protein-protein interaction, the conformational conversion of FlAsH-PrPsen to the prion disease-associated isoform, PrPres. PrP constructs with FlAsH/TC insertions at residues 90–96 but not 97–101 were converted to FlAsH-PrPres, identifying a boundary separating loosely versus compactly folded regions of PrPres. Our observations demonstrate that TC-scanning with the FlAsH/TC tag can be a versatile method for probing protein-protein interactions and folding processes. PMID:23943295

  4. [Renal scintigraphy with 99mTc-penicillamine].

    PubMed

    Lichte, H; Hör, G

    1975-02-01

    By application of 99mTc-Penicillamine in renal scintigraphy excellent scintigraphies of the kidneys, especially by using the gamma-camera, can be obtained, even in case of damaged renal function, up to an increase of creatinine in serum of about 7 mg %.

  5. High-Tc superconducting quantum interference devices: Status and perspectives

    NASA Astrophysics Data System (ADS)

    Yang, Hong-Chang; Chen, Ji-Chen; Chen, Kuen-Lin; Wu, Chiu-Hsien; Horng, Herng-Er; Yang, S. Y.

    2008-07-01

    In this paper, an overview of the current status of high-Tc superconducting quantum interference devices (SQUIDs), from device engineering to biomagnetic applications, is given. The authors offer a description of the current status of SQUID sensors, challenges encountered, and the solution of fabricating SQUID sensors with low flux noises. The current challenge that we face is to fabricate high-Tc SQUIDs that are not only more reproducible than the current technology but also capable of providing a high IcRn product and fabricating SQUID with high yield. Improvement of flux noises and fabrication yield in the integrated multichoices directly coupled SQUID magnetometer or gradiometer with series SQUID array are presented. High-Tc SQUID magnetometers exhibiting magnetic field sensitivity of ˜30-50fT/Hz1/2 or better at 100Hz was demonstrated by incorporating serial SQUID into the pickup loop of the magnetometers. New technologies currently being developed and applications for high-Tc SQUIDs are addressed.

  6. High Tc SQUID Detector for Magnetic Metallic Particles in Products

    NASA Astrophysics Data System (ADS)

    Tanaka, Saburo; Akai, Tomonori; Hatsukade, Yoshimi; Suzuki, Shuichi

    High-Tc superconducting quantum interference device (SQUID) is an ultra-sensitive magnetic sensor. After the discovery of the high-Tc superconducting materials, the performance of the high-Tc SQUID has been improved and stabilized. One strong candidate for application is a detection system of magnetic foreign matters in industrial products. There is a possibility that ultra-small metallic foreign matter has been accidentally mixed with industrial products such as lithium ion batteries. If this happens, the manufacturer of the product suffers a great loss recalling products. The outer dimension of metallic particles less than 100 micron cannot be detected using X-ray imaging, which is commonly used for the inspection. Therefore a highly sensitive system for small foreign matters is required. We developed detection systems based on high-Tc SQUID for industrial products. We could successfully detect small iron particles of less than 50 micron on a belt conveyer. These detection levels were hard to be achieved using conventional X-ray detection or other methods.

  7. Lymphoscintigraphy with Tc-99m-labeled dextran

    SciTech Connect

    Henze, E.; Schelbert, H.R.; Collins, J.D.; Najafi, A.; Barrio, J.R.; Bennett, L.R.

    1982-10-01

    Current agents for lymphoscintigraphy have limitations because of slow migration of the colloidal tracer from the injection site and the unknown effect of phagocytosis on the removal of the labelled particles. The usefulness of Tc-99m dextran (TcDx) with a molecular weight of 110,000 has been tested for lymphoscintigraphy. Computer-assisted dynamic imaging and serial blood sampling in 13 dog experiments demonstrated that the tracer cleared only by lymph drainage from an interstitial injection site. Following interdigital injection of 1.0 ml (0.5-5.0 mCi), TcDx reached the knee or elbow lymph nodes in 12.4 +/- 6.5 (1 s.d.) sec, and the inguinal or axillary lymph nodes in 98.0 +/- 42.3 sec. It cleared from the injection site with a half-time of 31.5 min. In a dog with surgically induced lymphedema, tracer migration was markedly delayed in the edematous leg and the radionuclide lymphoscintigram resembled the contrast lymphangiogram. Initial studies in man yielded high-quality radionuclide lymphograms of the leg, and the pelvic and paraaortic lymph nodes. We concluded that TcDx is very promising for lymphoscintigraphy.

  8. Lymphoscintigraphy with Tc-99m-labeled dextran

    SciTech Connect

    Henze, E.; Schelbert, H.R.; Collins, J.D.; Najafi, A.; Barrio, J.R.; Bennett, L.R.

    1982-10-01

    Current agents for lymphoscintigraphy have limitations because of slow migration of the colloidal tracers from the injection site and the unknown effect of phagocytosis on the removal of the labeled particles. The usefulness of Tc-99m dextran (TcDx) with a molecular weight of 110,000 has been tested for lymphoscintigraphy. Computer-assisted dynamic imaging and serial blood sampling in 13 dog experiments demonstrated that the tracer cleared only by lymph drainage from an interstitial injection site. Following interdigital injection of 1.0 ml (0.5-5.0 mCi), TcDx reached the knee or elbow lymph nodes in 12.4 +/- 6.5 (1 s.d.) sec, and the inguinal or axillary lymph nodes in 98.0 +/- 42.3 sec. It cleared from the injection site with a half-time of 31.5 min. In a dog with surgically induced lymphedema, tracer migration was markedly delayed in the edematous leg and the radionuclide lymphoscintigram resembled the contrast lymphangiogram. Initial studies in man yielded high-quality radionuclide lymphograms of the leg, and the pelvic and paraaortic lymph nodes. We conclude that TcDx is very promising for lymphoscintigraphy.

  9. Power Systems Development Facility Gasification Test Run TC09

    SciTech Connect

    Southern Company Services

    2002-09-30

    This report discusses Test Campaign TC09 of the Kellogg Brown & Root, Inc. (KBR) Transport Gasifier train with a Siemens Westinghouse Power Corporation (Siemens Westinghouse) particle filter system at the Power Systems Development Facility (PSDF) located in Wilsonville, Alabama. The Transport Gasifier is an advanced circulating fluidized-bed gasifier designed to operate as either a combustor or a gasifier in air- or oxygen-blown mode of operation using a particulate control device (PCD). The Transport Gasifier was operated as a pressurized gasifier during TC09 in air- and oxygen-blown modes. Test Run TC09 was started on September 3, 2002, and completed on September 26, 2002. Both gasifier and PCD operations were stable during the test run, with a stable baseline pressure drop. The oxygen feed supply system worked well and the transition from air to oxygen was smooth. The gasifier temperature varied between 1,725 and 1,825 F at pressures from 125 to 270 psig. The gasifier operates at lower pressure during oxygen-blown mode due to the supply pressure of the oxygen system. In TC09, 414 hours of solid circulation and over 300 hours of coal feed were attained with almost 80 hours of pure oxygen feed.

  10. Theory of Superconductivity in the High tc Materials

    NASA Astrophysics Data System (ADS)

    Anderson, P. W.

    The following sections are included: * INTRODUCTION * CONFINEMENT AND ITS CONSEQUENCES * PERTURBATION TREATMENT OF Tc; GREEN'S FUNCTIONS OF THE SUPERCONDUCTING STATE * HEURISTIC GAP EQUATION FOR THE INTERLAYER MECHANISM * A ROUGH PICTURE OF SOLUTIONS OF THE NEW GAP EQUATION * SURVEY OF THE EXPERIMENTAL PICTURE AND CORRELATION WITH THEORY * REFERENCES

  11. Peltier effect in the mixed state of high- Tc superconductors

    NASA Astrophysics Data System (ADS)

    Logvenov, G. Yu.; Ryazanov, V. V.; Ustinov, A. V.; Huebener, R. P.

    1991-04-01

    The Peltier and Seebeck effects in the mixed state of high- Tc superconductors are proportional to the resistivity due to flux motion. Therefore, both effects also show the broadening of the transition regime characteristic for these superconductors. The origin of the Peltier effect is discussed in detail, and the validity of the Thomson relation is confirmed, as expected.

  12. Amyloid goiter: preoperative scintigraphic diagnosis using Tc-99m pyrophosphate

    SciTech Connect

    Lee, V.W.; Rubinow, A.; Pehrson, J.; Skinner, M.; Cohen, A.S.

    1984-04-01

    Amyloid goiter is a rare clinical entity. The diagnosis is rarely made preoperatively because clinical and laboratory findings are nonspecific. The authors report two cases of amyloid goiter in whom the diagnosis was made preoperatively using Tc-99m pyrophosphate scintigraphy.

  13. Interdecadal changes in summer TC activity in East China Sea

    NASA Astrophysics Data System (ADS)

    Choi, Ki-Seon; Cha, Yu-Mi; Kang, Sung-Dae; Kim, Hae-Dong

    2015-04-01

    The study analyzed the time series of the tropical cyclone (TC) frequencies which passed through the East China Sea between July and September from 1963 to 2012. The result of applying the statistical change-point analysis to this time series shows that a climate regime shift occurred in 1983 when the TC frequencies which pass the East China Sea area started increasing. The study then analyzed the average difference after 1983 (1984-2012) and before 1983 (1963-1983). The TC genesis frequency shows a tendency in mainly appearing in the tropical and subtropical Northwestern Pacific between 1963 and 1983 and the southern part between 1984 and 2012. The TC passage frequency shows a pattern that the TCs move from the far northeast sea of Philippines and change direction to Korea and Japan, passing through the East China Sea between 1984 and 2012. Meanwhile, the TC passage frequency shows a pattern which moves from the far southeast sea of the Philippines to southern China in the west direction in the previous period (1963-1983). These TC movement patterns coincide with the development status of the subtropical western North Pacific high (SWNPH) which averages for each period. It shows that the SWNPH in the second period stays away from the SWNPH in the second period from the northeast direction, but that the SWNPH in the first period expands to western Taiwan. This study analyzes the difference between the two periods in the 500-hPa streamline to understand the changes in such TC activities in the two groups. The anomalous anticyclonic circulations centered in the southern part of Japan are fortified in most of the subtropical Northwestern Pacific. The anomalous southerlies from the anomalous circulations are outstanding in the East China Sea area, Korea, and Japan. Therefore, the TCs generated in the tropical and subtropical Northwestern Pacific move along with the anomalous steering flow (anomalous southwesterlies) and up toward the East China Sea area, Korea, and

  14. Study on 99mTc-MAG3 and 99mTc-DMSA renal accumulation using in vitro cellular model.

    PubMed

    Nový, Zbynĕk; Mandíková, Jana; Trejtnar, Frantisek

    2011-02-01

    Mercaptoacetyltriglycine (MAG3) and dimercaptosuccinic acid (DMSA) labelled with technetium-99m belongs to standard renal radiodiagnostics. However, the renal transport mechanisms responsible for their high renal uptake have not been fully explained. In addition, no in vitro experimental study comparing the renal uptake of these radiopharmaceuticals at the cellular level has not been performed. The investigation compared the 99mTc-MAG3 and 99mTc-DMSA renal uptake using primary rat renal cells and evaluated contribution of active and passive transport processes to the renal accumulation. The renal cells were isolated from the rat kidneys by means of the two-phase collagenase perfusion method. The used experimental model showed to be useful tool for such type of investigation. The results documented significant quantitative and qualitative differences in the accumulation of 99mTc-DMSA and 99mTc-MAG3 in the rat isolated cells. The found experimental data indicated several times higher uptake of 99mTc-MAG3 than that found in 99mTc-DMSA. 99mTc-MAG3 cellular uptake was substantially decreased when active, energy-dependent processes were inhibited. However, 99mTc-DMSA accumulation in the renal cells demonstrated only a minor dependency on energy. These findings demonstrate a very different character of the membrane transport determining 99mTc-DMSA and 99mTc-MAG3 renal accumulation.

  15. Tc1 and Tc2 effector cell therapy elicit long-term tumor immunity by contrasting mechanisms that result in complementary endogenous type 1 antitumor responses.

    PubMed

    Dobrzanski, Mark J; Reome, Joyce B; Hollenbaugh, Joseph A; Dutton, Richard W

    2004-02-01

    Cytolytic CD8(+) effector cells fall into two subpopulations based on cytokine secretion. Type 1 CD8(+) T cells (Tc1) secrete IFN-gamma, whereas type 2 CD8(+) T cells (Tc2) secrete IL-4 and IL-5. Both effector cell subpopulations display predominantly perforin-dependent cytolysis in vitro. Using an OVA-transfected B16 lung metastases model, we show that adoptively transferred OVA-specific Tc1 and Tc2 cells induce considerable suppression, but not cure, of pulmonary metastases. However, long-term tumor immunity prolonged survival times indefinitely and was evident by resistance to lethal tumor rechallenge. At early stages after therapy, protection by Tc2 and Tc1 effector cells were dependent in part on effector cell-derived IL-4, IL-5, and IFN-gamma, respectively. Whereas effector cell-derived perforin was not necessary. Over time the numbers of both donor cells diminished to low, yet still detectable, levels. Concomitantly, Tc1 and Tc2 effector cell therapies potentiated endogenous recipient-derived antitumor responses by inducing 1) local T cell-derived chemokines associated with type 1-like immune responses; 2) elevated levels of recipient-derived OVA tetramer-positive CD8 memory T cells that were CD44(high), CD122(+), and Ly6C(high) that predominantly produced IFN-gamma and TNF-alpha; and 3) heightened numbers of activated recipient-derived Th1 and Tc1 T cell subpopulations expressing CD25(+), CD69(+), and CD95(+) cell surface activation markers. Moreover, both Tc2 and Tc1 effector cell therapies were dependent in part on recipient-derived IFN-gamma and TNF-alpha for long-term survival and protection. Collectively, Tc1 and Tc2 effector cell immunotherapy mediate long-term tumor immunity by different mechanisms that subsequently potentiate endogenous recipient-derived type 1 antitumor responses.

  16. [Assessment of obstructive nephropathy using diuretic 99mTc-DTPA renogram and 99mTc-DMSA renoscintigraphy].

    PubMed

    Okamura, K; Takaba, H; Ito, K; Shimoji, T

    1987-12-01

    99mTc-DMSA and diuretic 99mTc-DTPA renoscintigraphy were performed on 51 kidneys suspected of obstructive nephropathy based on excretory urography to evaluate the residual renal function and the degree of urinary flow impairment respectively. We classified the response to diuretics into 6 patterns: I. normal, IIa. severely damaged renal function, IIb. slow RI excretion without urinary tract visualization (pattern II had no response to furosemide), IIIa. rapid elimination of tracer from the obstructed upper tract, IIIb. slow elimination, and IV. gradual tracer accumulation in the pelvicalyceal system with fairly well preserved renal function but no response. Hydronephrosis varied according to pattern type, in the ascending order of I, IIIa, IIIb and IV (p less than 0.05). Degree of hydronephrosis was inversely related to 99mTc-DMSA uptake, but without statistical significance. 99mTc-DMSA uptake was lower for pattern III as a whole (IIIa + (IIIb) than for pattern I (p less than 0.005), but there was no difference between IIIa and IIIb. Pattern IIa exhibited a significantly lower uptake than any of the other groups. (p less than 0.005) In contrast to previous views, we believe that pattern IIIa indicates a mild obstruction of urinary flow and impaired renal function. Consequently, assessment of obstructive nephropathy should not be based only on urodynamic study but also on differential renal function test.

  17. TC1 (C8orf4) is upregulated by cellular stress and mediates heat shock response.

    PubMed

    Park, Juhee; Jung, Yusun; Kim, Jungtae; Kim, Ka-Young; Ahn, Sang-Gun; Song, Kyuyoung; Lee, Inchul

    2007-08-24

    TC1 (C8orf4) is associated with aggressive behavior and poor survival in cancer. We have recently reported that it is a target gene of NF-kappaB and regulates the Wnt/beta-catenin pathway. Here, we show that TC1 is upregulated by various cellular stresses and mediates heat shock response. Heat shock and other cellular stresses including H2O2, 12-O-tetradecanoylphorbol 13-acetate (TPA), lipopolysaccharide (LPS), and UV enhance TC1 transcription in HeLa, KATO-III, HEK293T, and HK cells. TC1 protein then moves into the nuclei independently of NF-kappaB activation. TC1 upregulates heat shock proteins, and TC1-knockdown inhibits stress-induced downstream regulation significantly. Heat shock factor 1(HSF1) and TC1 upregulate each other, suggesting a potential positive feedback in the heat shock response regulation. Our data suggest that TC1 is a novel heat shock response regulator.

  18. Tc and Re Behavior in Borosilicate Waste Glass Vapor HydrationTests

    SciTech Connect

    McKeown, David A.; Buechele, Andrew C.; Lukens, Wayne W.; Shuh,David K.; Pegg, Ian L.

    2006-11-01

    Technetium (Tc), found in nuclear waste, is of particularconcern with regard to long-term waste storage because of its longhalf-life and high mobility in the environment. One method ofstabilization of such waste is through vitrification to produce a durableborosilicate glass matrix. The fate of Tc under hydrothermal conditionsin the Vapor Hydration Test (VHT) was studied to assess and possiblypredict the long-term rate of release of Tc from borosilicate wasteglass. For comparison, the fate of rhenium (Re), the preferrednon-radioactive surrogate for Tc, was similarly studied. X-ray absorptionspectroscopy (XAS) and scanning electron microscopy (SEM) measurementswere made on each original borosilicate glass and the correspondingsample after the VHT. Tc K-edge XAS indicates that, despite starting withdifferent Tc(IV) and Tc(VII) distributions in each glass, bothcorresponding VHT samples contain 100 percent Tc(IV). The Tc reductionwithin the VHT samples may be driven by simultaneous oxygen depletionfrom corrosion of the surrounding stainless steel vessel. From SEManalyses, both of the Tc-containing VHT samples show complete alterationof the original glass, significant Tc enrichment near the sample surface,and nearly complete depletion of Tc toward the sample center. XASindicates Tc(IV)O6 octahedra, possibly within gel-like amorphoussilicates in both VHT samples, where Tc-Tc correlations are observed inthe higher Tc-content VHT sample. Re LII-edge XAS and SEM indicate quitedifferent behavior for Re under VHT conditions. Re oxidation stateappears to be invariant with respect to the VHT treatment, whereperrhenate (Re(VII)) species are dominant in all Re-containing samplesinvestigated; Re2O7 concentrations are low NEAR the sample surface andincrease to approach the concentration of the un-reacted glass toward thesample center.

  19. The Tribolium castaneum cell line TcA: a new tool kit for cell biology.

    PubMed

    Silver, Kristopher; Jiang, Hongbo; Fu, Jinping; Phillips, Thomas W; Beeman, Richard W; Park, Yoonseong

    2014-10-30

    The red flour beetle, Tribolium castaneum, is an agriculturally important insect pest that has been widely used as a model organism. Recently, an adherent cell line (BCIRL-TcA-CLG1 or TcA) was developed from late pupae of the red flour beetle. Next generation transcriptome sequencing of TcA cells demonstrated expression of a wide variety of genes associated with specialized functions in chitin metabolism, immune responses and cellular and systemic RNAi pathways. Accordingly, we evaluated the sensitivity of TcA cells to dsRNA to initiate an RNAi response. TcA cells were highly sensitive to minute amounts of dsRNA, with a minimum effective dose of 100 pg/mL resulting in significant suppression of gene expression. We have also developed a plasmid containing two TcA-specific promoters, the promoter from the 40S ribosomal protein subunit (TC006550) and a bi-directional heat shock promoter (TcHS70) from the intergenic space between heat shock proteins 68a and b. These promoters have been employed to provide high levels of either constitutive (TC006550) or inducible (TcHS70) gene expression of the reporter proteins. Our results show that the TcA cell line, with its sensitivity to RNAi and functional TcA-specific promoters, is an invaluable resource for studying basic molecular and physiological questions.

  20. Photochemical behavior of the quadruply metal-metal bonded [Tc2Cl8]2– anion in acetonitrile

    DOE PAGES

    Burton-Pye, Benjamin P.; Poineau, Frederic; Bertoia, Julie; ...

    2016-09-23

    Here, the photochemical behavior of [Tc2Cl8]2– was investigated in acetonitrile. The speciation of Tc before and after irradiation at 254 nm was performed by UV-visible spectroscopy and electrospray ionization mass spectrometry (ESI-MS). Upon irradiation at 254 nm, [Tc2Cl8]2– was unstable, the scission of the TcTc unit occurred and the complex [TcCl4(CH3CN)2] was identified. The disappearance rate of [M2Cl8]2– (M = Tc, Re) under irradiation has been measured and was ~7.5 time faster for Tc than for Re.

  1. Power Systems Development Facility Gasification Test Campaing TC14

    SciTech Connect

    Southern Company Services

    2004-02-28

    In support of technology development to utilize coal for efficient, affordable, and environmentally clean power generation, the Power Systems Development Facility (PSDF) located in Wilsonville, Alabama, routinely demonstrates gasification technologies using various types of coals. The PSDF is an engineering scale demonstration of key features of advanced coal-fired power systems, including a KBR Transport Gasifier, a hot gas particulate control device (PCD), advanced syngas cleanup systems, and high pressure solids handling systems. This report details test campaign TC14 of the PSDF gasification process. TC14 began on February 16, 2004, and lasted until February 28, 2004, accumulating 214 hours of operation using Powder River Basin (PRB) subbituminous coal. The gasifier operating temperatures varied from 1760 to 1810 F at pressures from 188 to 212 psig during steady air blown operations and approximately 160 psig during oxygen blown operations.

  2. Bio-application of high-Tc SQUID magnetic sensor

    NASA Astrophysics Data System (ADS)

    Tanaka, Saburo; Aspanut, Zarina; Kurita, Hirofumi; Toriyabe, Chika; Hatuskade, Yoshimi; Katsura, Shinji

    2006-05-01

    We propose medical applications using ultra-small magnetic particles and a SQUID magnetic sensor. A high-Tc SQUID system for biological molecules (DNA) detection is one of that. This system is based on a hybridization process. Two strands in a DNA molecule are held together by hydrogen bonds between base pairs like a ladder. The two strands are referred to as being complementary to each other. One strand (sample DNA) was labeled with Fe 3O 4 ultra-small magnetic particles and the other (probe DNA) was anchored on a glass slide. Then they were hybridized each other on the slide. After washing the excess sample DNA, the hybridized DNA was evaluated in the presence of excitation AC field by high-Tc SQUID. The signal was initially proportional to the concentration of the sample DNA and then saturated. It means that the hybridization occurred successfully between the sample DNA and the probe DNA.

  3. Focal uptake of Tc-99m MDP in a gossypiboma.

    PubMed

    Thomas, Bejoy G; Silverman, Eugene D

    2008-04-01

    A 51-year-old Korean woman with a history of breast cancer underwent screening bone scintigraphy, which revealed minimal soft tissue uptake of Tc-99m methylene diphosphonate (MDP) in the right lower quadrant. CT and plain films confirmed that the uptake was due to a retained surgical sponge or gossypiboma. The incidence of gossypibomas has been reported at high as 1 in 1000 to 15,000 intra-abdominal operations. The natural progression of an aseptic gossypiboma is a foreign body reaction and granuloma formation. This inflammatory granulomatous reaction is the most likely cause of the extraosseous accumulation of Tc-99m MDP. This entity should be added to the already extensive list of etiologies of extraosseous MDP accumulation.

  4. NMR/MRI with hyperpolarized gas and high Tc SQUID

    DOEpatents

    Schlenga, Klaus; de Souza, Ricardo E.; Wong-Foy, Annjoe; Clarke, John; Pines, Alexander

    2000-01-01

    A method and apparatus for the detection of nuclear magnetic resonance (NMR) signals and production of magnetic resonance imaging (MRI) from samples combines the use of hyperpolarized inert gases to enhance the NMR signals from target nuclei in a sample and a high critical temperature (Tc) superconducting quantum interference device (SQUID) to detect the NMR signals. The system operates in static magnetic fields of 3 mT or less (down to 0.1 mT), and at temperatures from liquid nitrogen (77K) to room temperature. Sample size is limited only by the size of the magnetic field coils and not by the detector. The detector is a high Tc SQUID magnetometer designed so that the SQUID detector can be very close to the sample, which can be at room temperature.

  5. Bone metastasis on Tc99-m sestamibi myocardial perfusion scan

    PubMed Central

    Hatemi, Lachin; Jabi, Feraas

    2015-01-01

    A 75-year-old woman presented to our department for a stress myocardial perfusion imaging study with Tc99m-sestamibi. Incidental focal uptake, found in the left upper anterior chest, was initially felt to be located in the left breast. After additional single-photon CT imaging was performed the same day, extracardiac foci within the ribs, spine, and left lung (worrisome for active metastases) were shown to be present, with the initial focus located within a left rib rather than a breast. A review of previous radiographic and nuclear imaging studies confirmed metastatic disease from recurrent follicular thyroid cancer. Atypical focal extracardiac activity must be closely scrutinized for the possibility of malignancy, as Tc99m-sestamibi (in addition to being myocardium-avid) is tumor-avid. PMID:27190553

  6. Five Possible Reasons why HIGH-Tc Superconductivity is Stalled

    NASA Astrophysics Data System (ADS)

    Grether, M.; de Llano, M.

    2007-09-01

    Five commonly held premises considered questionable assumptions in the microscopic theory of superconductivity are discussed as possible reasons why the search appears to be stalled for a theoretical framework, admittedly ambitious, capable of predicting materials with critical temperatures Tc higher than the 1993 record of 164K in HgTlBaCaCuO (under pressure). We focus the dilemma as a whole in terms of a generalized Bose-Einstein condensation (GBEC) interpretation that includes and further extends BCS theory, as well as substantially enhancing its predicted Tcs within the electron-phonon mechanism producing pairing. The new GBEC model is an extension of the Friedberg-T.D. Lee 1989 boson-fermion BEC theory of high-Tc superconductors in that it includes hole pairs as well as electron pairs.

  7. Five Possible Reasons why HIGH-Tc Superconductivity is Stalled

    NASA Astrophysics Data System (ADS)

    Grether, M.; de Llano, M.

    Five commonly held premises considered questionable assumptions in the microscopic theory of superconductivity are discussed as possible reasons why the search appears to be stalled for a theoretical framework, admittedly ambitious, capable of predicting materials with critical temperatures Tc higher than the 1993 record of 164K in HgTlBaCaCuO (under pressure). We focus the dilemma as a whole in terms of a generalized Bose-Einstein condensation (GBEC) interpretation that includes and further extends BCS theory, as well as substantially enhancing its predicted Tcs within the electron-phonon mechanism producing pairing. The new GBEC model is an extension of the Friedberg-T.D. Lee 1989 boson-fermion BEC theory of high-Tc superconductors in that it includes hole pairs as well as electron pairs.

  8. Identification of pseudospin partner bands in Tc108

    NASA Astrophysics Data System (ADS)

    Xu, Q.; Zhu, S. J.; Hamilton, J. H.; Ramayya, A. V.; Hwang, J. K.; Qi, B.; Meng, J.; Peng, J.; Luo, Y. X.; Rasmussen, J. O.; Lee, I. Y.; Liu, S. H.; Li, K.; Wang, J. G.; Ding, H. B.; Gu, L.; Yeoh, E. Y.; Ma, W. C.

    2008-12-01

    High-spin structures in the neutron-rich Tc108 nucleus have been reinvestigated by measuring the prompt γ-rays from spontaneous fission of Cf252. A previously known collective band has been extended up to higher spin states and a new side band has been identified. These doublet bands are proposed as pseudospin partner bands with configurations π1/2+[431]⊗ν[312~5/2+,3/2+], which is a first identification in A~100 region. The particle-rotor model (PRM) was applied to calculate levels and B(M1)/B(E2) ratios of the bands in Tc108. The calculated results are in good agreement with the experimental values.

  9. Tc anisotropy and phase separation in strained Vanadium Dioxide films

    NASA Astrophysics Data System (ADS)

    Liu, Mengkun; Wagner, Martin; Abreu, Elsa; Kittiwatanakul, Salinporn; McLeod, Alexander; Goldflam, Michael; Fei, Zhe; Dai, Siyuan; Fogler, Michael; Lu, Jiwei; Wolf, Stuart; Averitt, Richard; Basov, D. N.

    2013-03-01

    We report Infrared near field study on strain induced transition temperature (Tc) anisotropy in vanadium dioxide (VO2) films via direct visualization of a spontaneous structural and electronic phase separation. The films are epitaxially grown on [110]R or [100]R TiO2 substrates and exhibit large uniaxial strain. By mapping the film topography with AFM and electronic percolation with Infrared scattering scanning near-field optical microscopy, a temperature dependent electron-lattice correlation can be clearly observed. Our work sheds a new light onto the nature of the Tc anomaly in metal-insulator transition and leads to the possibility of controlling the material's properties through strain induced phase separation.

  10. Portable exhausters POR-004 SKID B, POR-005 SKID C, POR-006 SKID D storage plan

    SciTech Connect

    Nelson, O.D.

    1997-09-04

    This document provides a storage plan for portable exhausters POR-004 SKID B, POR-005 SKID C, AND POR-006 SKID D. The exhausters will be stored until they are needed by the TWRS (Tank Waste Remediation Systems) Saltwell Pumping Program. The storage plan provides criteria for portable exhauster storage, periodic inspections during storage, and retrieval from storage.

  11. Comparison of the structural and magnetic properties of ground-state SrTcO 3 and CaTcO 3 from first principles

    NASA Astrophysics Data System (ADS)

    Ma, Chun-Lan; Zhou, Tong

    2012-01-01

    The generalized gradient approximation (GGA) plus on-site Coulomb interaction corrections (GGA+ U) method is employed for the total energies and electronic structure calculations of SrTcO 3 and CaTcO 3. G-type antiferromagnetic (G-AFM) is found to be ground state for both compounds, in consistence with the previous experimental results. The mechanism of Neel temperature of SrTcO 3 being higher than that of CaTcO 3 is explored. The insulating band gaps of SrTcO 3 and CaTcO 3 are found to be 1.71 eV and 1.74 eV, respectively. The magnetic moment of Tc1 is found to be 2.237μB in SrTcO 3 unit cell and 2.266μB in CaTcO 3 unit cell. Structural parameters and electronic structure of the two compounds are examined to explore the origin of their different electrical and magnetic characters.

  12. Discrepancies in brain perfusion SPECT findings between Tc-99m HMPAO and Tc-99m ECD: evaluation using dynamic SPECT in patients with hyperemia.

    PubMed

    Miyazawa, N; Koizumi, K; Mitsuka, S; Nukui, H

    1998-10-01

    Discrepancies have been reported between the findings of Tc-99m HMPAO and Tc-99m ECD brain perfusion SPECT imaging. This study investigated the discrepancies in the accumulation of these tracers using dynamic SPECT to detect the super early phase of distribution. Thirteen patients with luxury perfusion or high flow states were studied with both dynamic and standard SPECT using Tc-99m HMPAO and Tc-99m ECD within 1-3 days. Standard SPECT showed discrepancies in 6 of 13 patients. Patients with meningioma and cerebral thrombosis had increased accumulation of Tc-99m HMPAO and decreased uptake of Tc-99m ECD. Patients with arteriovenous malformation, subarachnoid hemorrhage, and cavernous angioma had decreased accumulation of both tracers, but to different degrees. Dynamic SPECT showed increased or normal accumulation (i.e., essentially no discrepancy) in the first few minutes. However, Tc-99m HMPAO had a longer retention time than Tc-99m ECD in the ensuing 5-10 minutes. Dynamic SPECT revealed a similar accumulation pattern but different washout rates for the two tracers. Tc-99m HMPAO might be a more suitable tracer to detect high flow states or luxury perfusion because the findings on standard SPECT were more in agreement with those of dynamic SPECT using this tracer.

  13. Different uptake of 99mTc-ECD adn 99mTc-HMPAO in the same brains: analysis by statistical parametric mapping.

    PubMed

    Hyun, Y; Lee, J S; Rha, J H; Lee, I K; Ha, C K; Lee, D S

    2001-02-01

    The purpose of this study was to investigate the differences between technetium-99m ethyl cysteinate dimer (99mTc-ECD) and technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO) uptake in the same brains by means of statistical parametric mapping (SPM) analysis. We examined 20 patients (9 male, 11 female, mean age 62+/-12 years) using 99mTc-ECD and 99mTc-HMPAO single-photon emission tomography (SPET) and magnetic resonance imaging (MRI) of the brain less than 7 days after onset of stroke. MRI showed no cortical infarctions. Infarctions in the pons (6 patients) and medulla (1), ischaemic periventricular white matter lesions (13) and lacunar infarction (7) were found on MRI. Split-dose and sequential SPET techniques were used for 99mTc-ECD and 99mTc-HMPAO brain SPET, without repositioning of the patient. All of the SPET images were spatially transformed to standard space, smoothed and globally normalized. The differences between the 99mTc-ECD and 99mTc-HMPAO SPET images were statistically analysed using statistical parametric mapping (SPM) 96 software. The difference between two groups was considered significant at a threshold of uncorrected P values less than 0.01. Visual analysis showed no hypoperfused areas on either 99mTc-ECD or 99mTc-HMPAO SPET images. SPM analysis revealed significantly different uptake of 99mTc-ECD and 99mTc-HMPAO in the same brains. On the 99mTc-ECD SPET images, relatively higher uptake was observed in the frontal, parietal and occipital lobes, in the left superior temporal lobe and in the superior region of the cerebellum. On the 99mTc-HMPAO SPET images, relatively higher uptake was observed in the medial temporal lobes, thalami, periventricular white matter and brain stem. These differences in uptake of the two tracers in the same brains on SPM analysis suggest that interpretation of cerebral perfusion is possible using SPET with 99mTc-ECD and 99mTc-HMPAO.

  14. Tc-99m pyrophosphate myocardial scanning in Chagas' disease

    SciTech Connect

    Goncalves da Rocha, A.F.; Meguerian, B.A.; Harbert, J.C.

    1981-04-01

    Chagas' disease is a serious protozoan infection affecting up to 20% of populations in some endemic areas. Myocarditis and cardiomyopathy occur in 50% of patients who go on to develop chronic Chagas's disease. We have studied a patient with no overt cardiac symptoms who revealed intense myocardial uptake of Tc-99m pyrophosphate. The significance of this finding in relation to early detection and progress of therapy is explored.

  15. Tc-99m pyrophosphate myocardial scanning in Chagas' disease

    SciTech Connect

    da Rocha, A.F.; Meguerian, B.A.; Harbert, J.C.

    1981-04-01

    Chagas' disease is a serious protozoan infection affecting up to 20% of populations in some endemic areas. Myocarditis and cardiomyopathy occur in 50% of patients who go on to develop chronic Chagas' disease. We have studied a patient with no overt cardiac symptoms who revealed intense myocardial uptake of Tc-99m pyrophosphate. The significance of this finding in relation to early detection and progress of therapy is explored.

  16. High-spin states in the 96Tc nucleus

    NASA Astrophysics Data System (ADS)

    Bucurescu, D.; Căta-Danil, Gh.; Căta-Danil, I.; Ivaşcu, M.; Mărginean, N.; Rusu, C.; Stroe, L.; Ur, C. A.; Gizon, A.; Gizon, J.; Nyakó, B.; Timár, J.; Zolnai, L.; Boston, A. J.; Joss, D. T.; Paul, E. S.; Semple, A. T.; Parry, C. M.

    High-spin states in the 96Tc nucleus have been studied with the reactions 82Se(19F,5nγ) at 68 MeV and Zn(36S,αpxn) at 130 MeV. Two γ-ray cascades (irregular bandlike structures) have been observed up to an excitation energy of about 10 MeV and spin 21-22?.

  17. High-spin states in the 97Tc nucleus

    NASA Astrophysics Data System (ADS)

    Bucurescu, D.; Gadea, A.; Căta-Danil, Ghe.; Căta-Danil, I.; Ivaşcu, M.; Mărginean, N.; Rusu, C.; Stroe, L.; Ur, C. A.

    High-spin states in the 97Tc nucleus have been studied by in-beam γ-ray spectroscopy with the reaction 82Se(19F,4nγ) at 68 MeV incident energy. Excited states have been observed up to about 8 MeV excitation and spin 43/2ℎ. The observed level scheme is compared with results of shell model calculations.

  18. Power Systems Development Facility Gasification Test Run TC08

    SciTech Connect

    Southern Company Services

    2002-06-30

    This report discusses Test Campaign TC08 of the Kellogg Brown & Root, Inc. (KBR) Transport Gasifier train with a Siemens Westinghouse Power Corporation (Siemens Westinghouse) particle filter system at the Power Systems Development Facility (PSDF) located in Wilsonville, Alabama. The Transport Gasifier is an advanced circulating fluidized-bed gasifier designed to operate as either a combustor or a gasifier in air- or oxygen-blown mode using a particulate control device (PCD). The Transport Gasifier was operated as a pressurized gasifier in air- and oxygen-blown modes during TC08. Test Run TC08 was started on June 9, 2002 and completed on June 29. Both gasifier and PCD operations were stable during the test run with a stable baseline pressure drop. The oxygen feed supply system worked well and the transition from air to oxygen blown was smooth. The gasifier temperature was varied between 1,710 and 1,770 F at pressures from 125 to 240 psig. The gasifier operates at lower pressure during oxygen-blown mode due to the supply pressure of the oxygen system. In TC08, 476 hours of solid circulation and 364 hours of coal feed were attained with 153 hours of pure oxygen feed. The gasifier and PCD operations were stable in both enriched air and 100 percent oxygen blown modes. The oxygen concentration was slowly increased during the first transition to full oxygen-blown operations. Subsequent transitions from air to oxygen blown could be completed in less than 15 minutes. Oxygen-blown operations produced the highest synthesis gas heating value to date, with a projected synthesis gas heating value averaging 175 Btu/scf. Carbon conversions averaged 93 percent, slightly lower than carbon conversions achieved during air-blown gasification.

  19. Clinical evaluation of /sup 99m/Tc-DMSA renogram

    SciTech Connect

    Van Poppel, H.; Vereecken, R.; Vekemans, K.; Verduyn, H.; Mortelmans, L.; de Roo, M.

    1985-04-01

    Two hundred-two /sup 99m/Tc-DMSA renograms for urologic problems were evaluated. Some technical aspects of the examination and the value of the scintigraphic depth estimation are discussed. Pre- and postoperative uptake values in patients with renal surgery and sequential postoperative examinations are considered. The value of DMSA renograms in predicting recovery in obstructive uropathy and in deciding to opt for conservative therapy or nephrectomy is discussed.

  20. Power Systems Development Facility Gasification Test Campaign TC24

    SciTech Connect

    Southern Company Services

    2008-03-30

    In support of technology development to utilize coal for efficient, affordable, and environmentally clean power generation, the Power Systems Development Facility (PSDF), located in Wilsonville, Alabama, routinely demonstrates gasification technologies using various types of coals. The PSDF is an engineering scale demonstration of key features of advanced coal-fired power systems, including a KBR Transport Gasifier, a hot gas particulate control device, advanced syngas cleanup systems, and high-pressure solids handling systems. This report summarizes the results of TC24, the first test campaign using a bituminous coal as the feedstock in the modified Transport Gasifier configuration. TC24 was conducted from February 16, 2008, through March 19, 2008. The PSDF gasification process operated for about 230 hours in air-blown gasification mode with about 225 tons of Utah bituminous coal feed. Operational challenges in gasifier operation were related to particle agglomeration, a large percentage of oversize coal particles, low overall gasifier solids collection efficiency, and refractory degradation in the gasifier solids collection unit. The carbon conversion and syngas heating values varied widely, with low values obtained during periods of low gasifier operating temperature. Despite the operating difficulties, several periods of steady state operation were achieved, which provided useful data for future testing. TC24 operation afforded the opportunity for testing of various types of technologies, including dry coal feeding with a developmental feeder, the Pressure Decoupled Advanced Coal (PDAC) feeder; evaluating a new hot gas filter element media configuration; and enhancing syngas cleanup with water-gas shift catalysts. During TC24, the PSDF site was also made available for testing of the National Energy Technology Laboratory's fuel cell module and Media Process Technology's hydrogen selective membrane.

  1. Weak Coupling Electron-Phonon for High Tc Superconductors

    NASA Astrophysics Data System (ADS)

    Labbe, J.

    1989-01-01

    Our opinion is that, in the high Tc copper oxides, the electronic correlations are not large enough to allow the localization of the electrons of the half-filled d-p sub-band. Thus, we treat them as itinerant electrons, in a bidimensional structure. And we show that, contrary to a widely held opinion, the electron-phonon interaction can induce high Tc superconductivity in these compounds, even in the weak coupling limit. This is due to the fact that, because of the bidimensionality, the electronic density of states is sharply peaked in the neighbourhood of the Fermi energy. A small coupling between nearest neighbouring CuO2 planes is sufficient to prevent a very large reduction of Tc by the critical fluctuations. The calculated isotope effect is much smaller than usually in the BCS theory. And, in our weak coupling theory, the antiferromagnetic (AF) phase is much more rapidly destabilized by dopping or internal charge transfer than the superconducting phase, which takes place when the AF phase has vanished.

  2. Induction magnetometer using a high-Tc superconductor coil

    NASA Astrophysics Data System (ADS)

    Sasada, Ichiro

    2010-05-01

    An induction magnetometer consisting of a search coil and an inverting operational amplifier is simple in structure and in signal transferring mechanism from the magnetic field input to the voltage output. Because this magnetometer is based on Faraday's law of induction, it has a lower cutoff frequency r/(2πL), where r is the resistance of the coil and L is its inductance. An attempt has been made to lower the cutoff frequency of the induction magnetometer by using a high-Tc superconductor coil. With a pancake coil (inner diameter ≈18 cm and outer diameter ≈23 cm, 92 turns, 3.23 mH) made of a Bismuth strontium calcium copper oxide (BSCCO) superconductor tape of 5 mm in width and 0.23 mm in thickness, the cutoff frequency achieved was 1.7 Hz which is much lower than that obtained with a bulky copper search coil which is typically in the range of 10-20 Hz. In the experiment, an inverting amplifier was made with a complementary metal-oxide semiconductor operational amplifier and was immersed in liquid nitrogen together with a BSCCO high-Tc superconducting coil. Discussion is made on the resolution of the induction magnetometer using a high-Tc superconductor search coil.

  3. Optimal High-TC Superconductivity in Cs3C60

    NASA Astrophysics Data System (ADS)

    Harshman, Dale; Fiory, Anthony

    The highest superconducting transition temperatures in the (A1-xBx)3C60 superconducting family are seen in the A15 and FCC structural phases of Cs3C60 (optimized under hydrostatic pressure), exhibiting measured values for near-stoichiometric samples of TC0 meas . = 37.8 K and 35.7 K, respectively. It is argued these two Cs-intercalated C60 compounds represent the optimal materials of their respective structures, with superconductivity originating from Coulombic e- h interactions between the C60 molecules, which host the n-type superconductivity, and mediating holes associated with the Cs cations. A variation of the interlayer Coulombic pairing model [Harshman and Fiory, J. Supercond. Nov. Magn. 28 ̲, 2967 (2015), and references therein] is introduced in which TC0 calc . ~ 1 / lζ , where l relates to the mean spacing between interacting charges on surfaces of the C60 molecules, and ζ is the average radial distance between the surface of the C60 molecules and the neighboring Cs cations. For stoichiometric Cs3C60, TC0 calc . = 38.08 K and 35.67 K for the A15 and FCC macrostructures, respectively; the dichotomy is attributable to differences in ζ.

  4. Power Systems Development Facility Gasification Test Campaing TC18

    SciTech Connect

    Southern Company Services

    2005-08-31

    In support of technology development to utilize coal for efficient, affordable, and environmentally clean power generation, the Power Systems Development Facility (PSDF) located in Wilsonville, Alabama, routinely demonstrates gasification technologies using various types of coals. The PSDF is an engineering scale demonstration of key features of advanced coal-fired power systems, including a KBR Transport Gasifier, a hot gas particulate control device (PCD), advanced syngas cleanup systems, and high pressure solids handling systems. This report details Test Campaign TC18 of the PSDF gasification process. Test campaign TC18 began on June 23, 2005, and ended on August 22, 2005, with the gasifier train accumulating 1,342 hours of operation using Powder River Basin (PRB) subbituminous coal. Some of the testing conducted included commissioning of a new recycle syngas compressor for gasifier aeration, evaluation of PCD filter elements and failsafes, testing of gas cleanup technologies, and further evaluation of solids handling equipment. At the conclusion of TC18, the PSDF gasification process had been operated for more than 7,750 hours.

  5. The influence of paddy soil drying on Tc insolubilization by bacteria.

    PubMed

    Wakae, Nao; Ishii, Nobuyoshi; Shikano, Shuichi; Uchida, Shigeo

    2006-05-01

    Tc insolubilization in four soils samples was compared by pre-incubating them in both dry and wet states, then measuring Tc concentrations in solution when the samples were saturated with an excess of water spiked with 99Tc. Soils pre-incubated in a dry state showed higher Tc insolubilization than soils incubated in a wet state. To clarify the difference in Tc insolubilization, Eh, bacterial abundances, and bacterial species compositions in the dry and wet ponding water samples were determined. For the wet ponding water samples, Eh values were forced to decrease, but no increase in Tc insolubilization was observed. The dry and wet ponding water samples had similar numbers of bacteria. However, denaturing gradient gel electrophoresis analysis revealed that they had different bacterial species compositions. These results suggested the difference in bacterial species compositions would account for the difference in Tc insolubilization.

  6. The determination of relative renal function in a pediatric population using Tc-99m DTPA and Tc-99m DMSA

    SciTech Connect

    Rosen, P.R.; Kuruc, A.; Treves, S.T.

    1985-05-01

    Three methods for evaluating relative renal function in a pediatric population were compared. The clinical and nuclear medicine data of 73 patients were reviewed. Pertinent data included patient age, serum creatinine and the referral diagnosis (reflux, hypertension, obstructive uropathy). Time activity curves for renal regions of interest (ROI) were obtained by renography with Tc-99m DTPA, and deconvolved by an externally detected blood pool curve Furosemide was then administered to evaluate the renal collecting system (if indicated). This was followed by DMSA administration. Relative function was determined in 3 ways: 1) Accumulated renal DTPA activity 60-120 sec. following injection. 2) Amplitude of the tubular phase of the deconvolved renal curve and, 3) Accumulated Tc-99m DMSA activity in renal ROI 4 or 24 hrs. post-injection. Regression analysis revealed: 1) The basic relationship of relative functional data obtained by all three methods was not affected by creatinine, age or other factors. 2) The relationship between the three methods is linear and highly correlated. 3) The DMSA values may be predicted from either method of analyzing the DTPA study using appropriate predictor equations. The authors conclude that Tc-99m DMSA, due to its higher cost and more radiation exposure should not be used for the routine evaluation of relative renal function.

  7. Differentiation of Trypanosoma cruzi I (TcI) and T. cruzi II (TcII) genotypes using genes encoding serine carboxypeptidases.

    PubMed

    de Araújo, Catarina Andréa Chaves; Mayer, Christoph; Waniek, Peter Josef; Azambuja, Patricia; Jansen, Ana Maria

    2016-11-01

    The parasite Trypanosoma cruzi (Kinetoplastida, Trypanosomatidae) can be classified based on biochemical and molecular markers, into six lineages or discrete typing units (DTUs), T. cruzi I-VI (TcI-VI), from which TcI and TcII are the parental genotypes. Trying to understand the dispersion of the subpopulations of T. cruzi in nature and its complex transmission cycles, the serine carboxypeptidase genes of T. cruzi were used as a molecular marker in the present study. DTUs of 25 T. cruzi isolates derived from different hosts and from different regions of Brazil were classified. Using specific primers, the complete serine carboxypeptidase open reading frame of 1401 bp was sequenced. The obtained data shows significant differences in the sequences of TcI and TcII. The analysis of the T. cruzi significantly different serine carboxypeptidase genes allowed distinguishing between the parental DTUs TcI to TcII and the hybrid DTU TcVI which grouped within the latter branch. The sequence diversity within the T. cruzi subpopulations was rather low. The analysis using the genes encoding proteases seems to be an interesting approach for the reconstruction of the origin and genotype evolution of T. cruzi.

  8. Infection with Trypanosoma cruzi TcII and TcI in free-ranging population of lion tamarins (Leontopithecus spp): an 11-year follow-up

    PubMed Central

    Lisboa, Cristiane Varella; Monteiro, Rafael Veríssimo; Martins, Andreia Fonseca; Xavier, Samantha Cristina das Chagas; Lima, Valdirene dos Santos; Jansen, Ana Maria

    2015-01-01

    Here, we present a review of the dataset resulting from the 11-years follow-up of Trypanosoma cruzi infection in free-ranging populations of Leontopithecus rosalia (golden lion tamarin) and Leontopithecus chrysomelas (golden-headed lion tamarin) from distinct forest fragments in Atlantic Coastal Rainforest. Additionally, we present new data regarding T. cruzi infection of small mammals (rodents and marsupials) that live in the same areas as golden lion tamarins and characterisation at discrete typing unit (DTU) level of 77 of these isolates. DTU TcII was found to exclusively infect primates, while TcI infected Didelphis aurita and lion tamarins. The majority of T. cruzi isolates derived from L. rosalia were shown to be TcII (33 out 42) Nine T. cruzi isolates displayed a TcI profile. Golden-headed lion tamarins demonstrated to be excellent reservoirs of TcII, as 24 of 26 T. cruzi isolates exhibited the TcII profile. We concluded the following: (i) the transmission cycle of T. cruzi in a same host species and forest fragment is modified over time, (ii) the infectivity competence of the golden lion tamarin population fluctuates in waves that peak every other year and (iii) both golden and golden-headed lion tamarins are able to maintain long-lasting infections by TcII and TcI. PMID:25946156

  9. Peripheral Tc17 and Tc17/Interferon-γ Cells are Increased and Associated with Lung Function in Patients with Chronic Obstructive Pulmonary Disease

    PubMed Central

    Xu, Wei-Han; Hu, Xiao-Ling; Liu, Xiao-Fang; Bai, Peng; Sun, Yong-Chang

    2016-01-01

    Background: Chronic obstructive pulmonary disease (COPD) is characterized by progressive loss of lung function and local and systemic inflammation, in which CD8+ T-cells are believed to play a key role. Activated CD8+ T-cells differentiate into distinct subpopulations, including interferon-γ (IFN-γ)-producing Tc1 and interleukin (IL)-17-producing Tc17 cells. Recent evidence indicates that Tc17 cells exhibit considerable plasticity and may convert into IL-17/IFN-γ-double producing (Tc17/IFN-γ) cells when driven by inflammatory conditions. The aim of this study was to investigate the Tc17/IFN-γ subpopulation in peripheral blood of patients with COPD and to evaluate their potential roles in this disease. Methods: Peripheral blood samples were collected from 15 never-smokers, 23 smokers with normal lung function, and 25 patients with COPD (Global Initiative for Chronic Obstructive Lung Disease 2–4). Proportions of the IL-17/IFN-γ-double expressing subpopulation were assessed using flow cytometry. Plasma concentrations of cytokines favoring Tc17/IFN-γ differentiation were measured by enzyme-linked immunosorbent assay. Results: Patients with COPD had higher proportions of Tc17 cells and Tc17/IFN-γ cells in the peripheral blood than smokers and never-smokers. The plasticity of Tc17 cells was higher than that of Th17 cells. The percentages of Tc17 cells and Tc17/IFN-γ cells showed negative correlations with forced expiratory volume in 1 s % predicted value (r = −0.418, P = 0.03; r = −0.596, P = 0.002, respectively). The plasma concentrations of IL-6, transforming growth factor-β1, and IL-12 were significantly higher in patients with COPD compared with smokers and never-smokers. Conclusions: Peripheral Tc17 cells are increased and more likely to convert to Tc17/IFN-γ cells in COPD, suggesting that Tc17 cell plasticity may be involved in persistent inflammation of the disease. PMID:27064034

  10. A Novel Ternary Ligand System Useful for Preparation of Cationic 99mTc-Diazenido Complexes and 99mTc-Labeling of Small Biomolecules

    PubMed Central

    Kim, Young-Seung; He, Zhengjie; Hsieh, Wen-Yuan; Liu, Shuang

    2008-01-01

    This report describes a novel ternary ligand system composed of a phenylhydrazine, a crown ether-containing dithiocarbamate (DTC) and a PNP-type bisphosphine (PNP). The combination of three different ligands with 99mTc results in cationic 99mTc-diazenido complexes,[99mTc(NNAr)(DTC)(PNP)]+, with potential radiopharmaceuticals for heart imaging. Synthesis of cationic 99mTc-diazenido complexes can be accomplished in two steps with high yield. For example, the reaction of phenylhydrazine with 99mTcO4− at 100 °C in the presence of excess stannous chloride and 1,2-diaminopropane-N,N,N’,N’-tetraacetic acid (PDTA) results in the [99mTc(NNPh)(PDTA)n] intermediate, which then reacts with sodium N-(dithiocarbamato)-2-aminimethyl-15-Crown-5 (L4) and N,N-bis[2-(bis(3-ethoxypropyl)phosphino)ethyl]ethoxy-ethylamine (PNP6) at 100 °C for 15 min to give the complex, [99mTc(NNPh)(L4)(PNP6)]+ in high yield (> 90%). Cationic complexes [99mTc(NNPh)(DTC)(PNP)]+ are stable for ≥6 h. Their composition was determined to be 1:1:1:1 for Tc:NNPh:DTC:PNP using the mixed-ligand experiments on the tracer (99mTc) level, and was further confirmed by the ESI-MS spectral data of a model compound [Re(NNPh)(L4)(L6)]+. It was found that both DTCs and bisphosphines have a significant impact on the lipophilicity of their cationic 99mTc-diazenido complexes. Results from a 99mTc-labeling efficiency experiment showed that 4-hydrazinobenzoic acid (HYBA) might be useful as a bifunctional coupling agent for 99mTc-labeling of small biomolecules. However, the 99mTc-labeling efficiency of HYBA is much lower than that of 6-hydrazinonicotinic acid (HYNIC) with tricine and trisodium triphenylphosphine-3,3’,3”-trisulfonate (TPPTS) as coligands. PMID:16536480

  11. TcI, TcII and TcVI Trypanosoma cruzi samples from Chagas disease patients with distinct clinical forms and critical analysis of in vitro and in vivo behavior, response to treatment and infection evolution in murine model.

    PubMed

    Oliveira, Maykon Tavares de; Branquinho, Renata Tupinambá; Alessio, Gláucia Diniz; Mello, Carlos Geraldo Campos; Nogueira-de-Paiva, Nívia Carolina; Carneiro, Cláudia Martins; Toledo, Max Jean de Ornelas; Reis, Alexandre Barbosa; Martins-Filho, Olindo Assis Martins; Lana, Marta de

    2017-03-01

    The clonal evolution of Trypanosoma cruzi sustains scientifically the hypothesis of association between parasite's genetic, biological behavior and possibly the clinical aspects of Chagas disease in patients from whom they were isolated. This study intended to characterize a range of biological properties of TcI, TcII and TcVI T. cruzi samples in order to verify the existence of these associations. Several biological features were evaluated, including in vitro epimastigote-growth, "Vero"cells infectivity and growth, along with in vivo studies of parasitemia, polymorphism of trypomastigotes, cardiac inflammation, fibrosis and response to treatment by nifurtimox during the acute and chronic murine infection. The global results showed that the in vitro essays (acellular and cellular cultures) TcII parasites showed higher values for all parameters (growth and infectivity) than TcVI, followed by TcI. In vivo TcII parasites were more virulent and originated from patients with severe disease. Two TcII isolates from patients with severe pathology were virulent in mice, while the isolate from a patient with the indeterminate form of the disease caused mild infection. The only TcVI sample, which displayed low values in all parameters evaluated, was also originated of an indeterminate case of Chagas disease. Response to nifurtimox was not associated to parasite genetic and biology, as well as to clinical aspects of human disease. Although few number of T. cruzi samples have been analyzed, a discreet correlation between parasite genetics, biological behavior in vitro and in vivo (murine model) and the clinical form of human disease from whom the samples were isolated was verified.

  12. TC1(C8orf4) regulates hematopoietic stem/progenitor cells and hematopoiesis.

    PubMed

    Jung, Yusun; Kim, Minsung; Soh, Hyunsu; Lee, Soyoung; Kim, Jungtae; Park, Surim; Song, Kyuyoung; Lee, Inchul

    2014-01-01

    Hematopoiesis is a complex process requiring multiple regulators for hematopoietic stem/progenitor cells (HSPC) and differentiation to multi-lineage blood cells. TC1(C8orf4) is implicated in cancers, hematological malignancies and inflammatory activation. Here, we report that Tc1 regulates hematopoiesis in mice. Myeloid and lymphoid cells are increased markedly in peripheral blood of Tc1-deleted mice compared to wild type controls. Red blood cells are small-sized but increased in number. The bone marrow of Tc1-/- mice is normocellular histologically. However, Lin-Sca-1+c-Kit+ (LSK) cells are expanded in Tc1-/- mice compared to wild type controls. The expanded population mostly consists of CD150-CD48+ cells, suggesting the expansion of lineage-restricted hematopoietic progenitor cells. Colony forming units (CFU) are increased in Tc1-/- mice bone marrow cells compared to controls. In wild type mice bone marrow, Tc1 is expressed in a limited population of HSPC but not in differentiated cells. Major myeloid transcriptional regulators such as Pu.1 and Cebpα are not up-regulated in Tc1-/- mice bone marrow. Our findings indicate that TC1 is a novel hematopoietic regulator. The mechanisms of TC1-dependent HSPC regulation and lineage determination are unknown.

  13. /sup 99m/Tc-glucoheptonate for quantitation of differential renal function

    SciTech Connect

    Ziessman, H.A.; Balseiro, J.; Fahey, F.H.; Le, T.V.; Dubiansky, V.

    1987-05-01

    Differential renal function was calculated by using /sup 99m/Tc-glucoheptonate (Tc-GH) in 51 patients. Computer-acquired background-corrected individual renal function was calculated by using both the 1-3-min uptake counts and the 2-4-hr delayed static counts. The degree of correlation between the two was high (r = .96). An equally high correlation was noted in 16 children who were 12 years old or younger, in 15 patients with renal size disparity greater than 60/40%, and in six patients with abnormal creatinine clearances. Ten patients had a 30-min dynamic /sup 99m/Tc-DTPA study followed immediately by the injection of Tc-GH and acquisition of delayed static images 2-4 hr later. A high degree of correlation (r = .99) was seen between the 1-3-min differential function obtained by using Tc-DTPA and the 2-4-hr delayed differential function obtained by using Tc-GH. This study shows that Tc-GH is a clinically useful and valid tool for calculation of differential renal function and that Tc-GH combines many of the best aspects of Tc-DTPA and Tc-DMSA.

  14. Nuclear shape and structure in neutron-rich {sup 110,111}Tc

    SciTech Connect

    Luo, Y. X.; Hamilton, J. H.; Ramayya, A. V.; Hwang, J. K.; Gore, P. M.; Jones, E. F.; Fong, D.; Rasmussen, J. O.; Lee, I. Y.; Stefanescu, I.; Che, X. L.; Zhu, S. J.; Wu, S. C.; Ginter, T. N.; Ma, W. C.; Ter-Akopian, G. M.; Daniel, A. V.; Stoyer, M. A.; Donangelo, R.; Gelberg, A.

    2006-08-15

    The high-spin nuclear structure of Tc isotopes is extended to more neutron-rich regions based on the measurements of prompt {gamma} rays from the spontaneous fission of {sup 252}Cf at the Gammasphere. The high-spin level scheme of N=67 neutron-rich {sup 110}Tc (Z=43) is established for the first time, and that of {sup 111}Tc is extended and expanded. The ground band of {sup 111}Tc reaches the band-crossing region, and the new observation of the weakly populated {alpha}=-1/2 member of the band provides important information on signature splitting. The systematics of band crossings in the isotopic and isotonic chains and a CSM calculation suggest that the band crossing of the ground band of {sup 111}Tc is due to alignment of a pair of h{sub 11/2} neutrons. The best fit to signature splitting, branching ratios, and excitations of the ground band of {sup 111}Tc by the rigid triaxial rotor plus particle model calculations result in a shape of {epsilon}{sub 2}=0.32 and {gamma}=-26 deg. for this nucleus. Its triaxiality is larger than that of {sup 107,109}Tc, which indicates increasing triaxiality in Tc isotopes with increasing neutron number. The identification of the weakly populated K+2 satellite band provides strong evidence for the large triaxiality of {sup 111}Tc. In {sup 110}Tc, the four lowest-lying levels observed are very similar to those in {sup 108}Tc. At an excitation of 478.9 keV above the lowest state observed, ten states of a {delta}I=1 band are observed. This band of {sup 110}Tc is very analogous to the {delta}I=1 bands in {sup 106,108}Tc, but it has greater and reversal signature splitting at higher spins.

  15. (99m)Tc-MAG3: Image Wisely.

    PubMed

    Taylor, Andrew T; Folks, Russell D; Rahman, A K M Fazlur; Polsani, Aruna; Dubovsky, Eva V; Halkar, Raghuveer; Manatunga, Amita

    2017-02-17

    Purpose To determine if commonly administered doses of technetium 99m ((99m)Tc) mertiatide (MAG3) in the range of 300-370 MBq (approximately 8-10 mCi) contribute to image interpretation and justify the resulting radiation exposure. Materials and Methods The respective institutional review boards approved this HIPAA-compliant study and waived informed consent. Baseline and furosemide (99m)Tc-MAG3 imaging examinations in 50 patients suspected of having renal obstruction and 48 patients suspected of having renovascular hypertension (RVH) were randomly selected from archived databases and were independently scored by three experienced readers without access to 2-second flow images. Readers were blinded to their original scores, and then they rescored each examination with access to high-activity 2-second flow images. Relative renal function was determined after a low activity (62.9 MBq ± 40.7) baseline acquisition for RVH and a high activity (303.4 MBq ± 48.1) acquisition after administration of enalaprilat. Data were analyzed by using random effects analysis of variance and mean and standard error of the mean for the difference between sets of scores and the difference between relative function measurements. Results There was no significant difference in the scores without flow images compared with blinded scores with high-activity flow images for patients suspected of having obstruction (P = .80) or RVH (P = .24). Moreover, there was no significant difference in the relative uptake measurements after administration of low and high activities (P > .99). Conclusion Administered doses of (99m)Tc-MAG3 in the range of 300-370 MBq (approximately 8-10 mCi) do not affect the relative function measurements or contribute to interpretation of images in patients suspected of having RVH or obstruction compared with administration of lower doses; unnecessary radiation exposure can be avoided by administering doses in the range of 37-185 MBq as recommended incurrent guidelines

  16. Bismuth cuprate high-Tc superconductors using cationic substitution

    NASA Astrophysics Data System (ADS)

    Tarascon, J.-M.; Barboux, P.; Hull, G. W.; Ramesh, R.; Greene, L. H.; Giroud, M.; Hegde, M. S.; McKinnon, W. R.

    1989-03-01

    The Bi4Sr4Ca2-xRxCu4BOy materials (R is a rare-earth element) were studied to determine their structural and physical properties. For most of the rare-earth elements, a complete solid solution exists up to x=2. Below x=0.5,Tc is not affected and for each added rare-earth element we find that about 0.5 oxygen atom is added to the structure. However, the structural modulation observed along the b axis for the undoped material persists and remains of the same amplitude for the rare-earth-doped samples. When more than one R(x>=1) is substituted, Tc is depressed and the compound becomes semiconducting beyond x=1.5. The depression in the Tc from 85 K (x=0) to less than 4.2 K (x=1.5) correlates to a decrease in the formal valence of copper and is independent whether the rare-earth element is magnetic or nonmagnetic. No evidence for magnetic ordering over the range of temperature 1.7-400 K has been observed in all the substituted compounds. The substitution for Cu by 3d metals or for Sr by rare-earth elements fails for the 85-K Bi phase but succeeds for the 10-K Bi phase. Consequently, the following series Bi2Sr2Cu1-xMxOy (M=Fe, Co) and Bi2RCaCuOy (R=La, Pr, Nd, Sm) were made for study. These substitutions result in an uptake of oxygen (0.5 for each substituted element). But the materials become semiconducting even though the formal valence of Cu remains greater than 2. An antiferromagnetic transition at 140 K has been found for the Co sample for which Co is found to be in the +3 state.

  17. Nernst effect, fluctuation diamagnetism and vortices above Tc in cuprates

    NASA Astrophysics Data System (ADS)

    Phuan Ong, N.

    2007-03-01

    Nernst-effect and torque magnetometry experiments have provided evidence that, in the hole-doped cuprates, long-range phase coherence vanishes at the critical temperature Tc, while the pair condensate survives to a much higher ``onset" temperature Tonset. In the Nernst experiment, the vortex current produced by a gradient generates a Josephson E-field perpendicular to the applied field H. In cuprates, this large Nernst signal eN persists to Tonset˜ 130 K. Extensive Nernst experiments in the cuprates LSCO, Bi 2201, and 2212 yield a 3D phase diagram (x,T,H) in fields up to 45 T. This picture has been confirmed by high-resolution torque magnetometry. In a tilted H, local planar supercurrents associated with vortices above Tc produce a torque that deflects a cantilever. At each T, the diamagnetic magnetization inferred matches the field profile of the Nernst eN. The high-resolution measurement of the diamagnetic susceptibility χ over 5 field decades uncovers an unusual, fragile ``London rigidity'' that exists in the pseudogap state of Bi 2212 and 2201. The magnetization curves below Tc also provide a reliable determination of the upper critical field Hc2 which is found to scale linearly with Tonset. I will also preview evidence for pairing without phase coherence at 0.35 K in LSCO for x < xc in fields to 30-45 T. In collaboration with Yayu Wang, Lu Li, Joseph G. Checkelsky, Michael Naughton, Seiki Komiya, Shimpei Ono, Yoichi Ando, Shin-ichi Uchida and Genda Gu.

  18. Investigation of TC-1 flight failure using power spectral analysis

    NASA Technical Reports Server (NTRS)

    Lorenzo, C. F.

    1976-01-01

    During the Titan Centaur 1 test flight a failure involving at least one of the Centaur propellant boost pumps occurred. Also, neither of the boost pump speed instruments indicated pump rotation. Accelerometer data from the Titan Centaur 1 flight failure were analyzed using power spectral density methods to determine boost pump speed during attempted starts of the Centaur. The technique was demonstrated on a reference flight. The hydrogen boost pump speed transient was determined for the TC-1 flight. Other trends are seen in the data. However, these are not believed to be the oxygen boost pump. Discussion of data enhancement techniques is also presented.

  19. Applications using high-Tc superconducting terahertz emitters

    PubMed Central

    Nakade, Kurama; Kashiwagi, Takanari; Saiwai, Yoshihiko; Minami, Hidetoshi; Yamamoto, Takashi; Klemm, Richard A.; Kadowaki, Kazuo

    2016-01-01

    Using recently-developed THz emitters constructed from single crystals of the high-Tc superconductor Bi2Sr2CaCu2O8+δ, we performed three prototype tests of the devices to demonstrate their unique characteristic properties for various practical applications. The first is a compact and simple transmission type of THz imaging system using a Stirling cryocooler. The second is a high-resolution Michelson interferometer used as a phase-sensitive reflection-type imaging system. The third is a system with precise temperature control to measure the liquid absorption coefficient. The detailed characteristics of these systems are discussed. PMID:26983905

  20. TC-Investigator: A Matlab Program to Explore Pseudosections

    NASA Astrophysics Data System (ADS)

    Pearce, Mark; Gazley, Michael; White, Alistair

    2014-05-01

    Forward modelling of bulk rock compositions to constrain pressures and temperatures of metamorphism based on mineral assemblage is a commonly used technique. The pseudosections produced contain a wealth of information about predicted mineral compositions and abundances that goes far beyond variations in mineral assemblage. A grid of these variations can be contoured using Gibbs free energy minimisation software (such as Theriak-Domino) or precise isopleths calculated for specific quantities in THERMOCALC. We have produced a new piece of software called TC-Investigator that amalgamates these approaches to provide a relatively quick and user friendly way to contour all compositional parameters and mineral modes across a THERMOCALC pseudosection. TC-Investigator takes the postscript pseudosection diagram and creates a grid of points at a user-specified resolution. THERMOCALC is then used to calculate the equilibrium mineral assemblage at each point using an initial starting guess provided by the user (this can be calculated during initial pseudosection calculation). Once all points have been tried, any that failed to calculate are re-tried using interpolated starting guess values from the surrounding points. This procedure is iterated until no more solutions are found. Any remaining unsolved points are then interpolated numerically from surrounding solutions to produce a fully quantified set of mineral modes and compositions. Following calculation, the dataset can be contoured and output as figures, output as a Matlab readable binary structure or selected compositions written to an ASCII text file. Compositional maps created by TC-Investigator have the power to inform the user about compositional variables that are not conventionally considered. The automated calculation method makes it easy to investigate all variables in one go. For example, in metapelitic rocks, garnet shows the variations in composition that are usually contoured, however, these couple to

  1. Power Systems Development Facility Gasification Test Run TC10

    SciTech Connect

    Southern Company Services

    2002-12-30

    This report discusses Test Campaign TC10 of the Kellogg Brown & Root, Inc. (KBR) Transport Gasifier train with a Siemens Westinghouse Power Corporation (Siemens Westinghouse) particle filter system at the Power Systems Development Facility (PSDF) located in Wilsonville, Alabama. The Transport Gasifier is an advanced circulating fluidized-bed gasifier designed to operate as either a combustor or a gasifier in air- or oxygen-blown mode of operation using a particulate control device (PCD). The Transport Gasifier was operated as a pressurized gasifier during TC10 in air- (mainly for transitions and problematic operations) and oxygen-blown mode. Test Run TC10 was started on November 16, 2002, and completed on December 18, 2002. During oxygen-blown operations, gasifier temperatures varied between 1,675 and 1,825 F at pressures from 150 to 180 psig. After initial adjustments were made to reduce the feed rate, operations with the new fluidized coal feeder were stable with about half of the total coalfeed rate through the new feeder. However, the new fluidized-bed coal feeder proved to be difficult to control at low feed rates. Later the coal mills and original coal feeder experienced difficulties due to a high moisture content in the coal from heavy rains. Additional operational difficulties were experienced when several of the pressure sensing taps in the gasifier plugged. As the run progressed, modifications to the mills (to address processing the wet coal) resulted in a much larger feed size. This eventually resulted in the accumulation of large particles in the circulating solids causing operational instabilities in the standpipe and loop seal. Despite problems with the coal mills, coal feeder, pressure tap nozzles and the standpipe, the gasifier did experience short periods of stability during oxygenblown operations. During these periods, the syngas quality was high. During TC10, the gasifier gasified over 609 tons of Powder River Basin subbituminous coal and

  2. Detecting defect in cast iron using high- TC SQUID

    NASA Astrophysics Data System (ADS)

    He, D. F.; Yoshizawa, M.; Oyama, Y.; Nakamura, M.

    2004-10-01

    For eddy-current NDE, due to the big permeability of ferromagnetic material, low testing frequency is needed to detect defects in it. SQUID has advantages in low frequency eddy current NDE. But the large magnetic field produced by ferromagnetic material often exceeds the dynamic range of general SQUID system. We developed a mobile high- TC SQUID system, with which, the dc and low-frequency magnetic field could be compensated well. Using our mobile SQUID system, the magnetic field produced by the cast iron could be compensated well and the defect in it could be successfully detected.

  3. Scanning high-Tc SQUID imaging system for magnetocardiography

    NASA Astrophysics Data System (ADS)

    Yang, Hong-Chang; Wu, Tsung-Yeh; Horng, Herng-Er; Wu, Chau-Chung; Yang, S. Y.; Liao, Shu-Hsien; Wu, Chiu-Hsien; Jeng, J. T.; Chen, J. C.; Chen, Kuen-Lin; Chen, M. J.

    2006-05-01

    A scanning magnetocardiography (MCG) system constructed from SQUID sensors offers potential to basic or clinical research in biomagnetism. In this work, we study a first order scanning electronic high-Tc (HTS) SQUID MCG system for biomagnetic signals. The scanning MCG system was equipped with an x-y translation bed powered by step motors. Using noise cancellation and μ-metal shielding, we reduced the noise level substantially. The established scanning HTS MCG system was used to study the magnetophysiology of hypercholesterolaemic (HC) rabbits. The MCG data of HC rabbits were analysed. The MCG contour map of HC rabbits provides experimental models for the interpretation of human cardiac patterns.

  4. 99mTc: Labeling Chemistry and Labeled Compounds

    NASA Astrophysics Data System (ADS)

    Alberto, R.; Abram, U.

    This chapter reviews the radiopharmaceutical chemistry of technetium related to the synthesis of perfusion agents and to the labeling of receptor-binding biomolecules. To understand the limitations of technetium chemistry imposed by future application of the complexes in nuclear medicine, an introductory section analyzes the compulsory requirements to be considered when facing the incentive of introducing a novel radiopharmaceutical into the market. Requirements from chemistry, routine application, and market are discussed. In a subsequent section, commercially available 99mTc-based radiopharmaceuticals are treated. It covers the complexes in use for imaging the most important target organs such as heart, brain, or kidney. The commercially available radiopharmaceuticals fulfill the requirements outlined earlier and are discussed with this background. In a following section, the properties and perspectives of the different generations of radiopharmaceuticals are described in a general way, covering characteristics for perfusion agents and for receptor-specific molecules. Technetium chemistry for the synthesis of perfusion agents and the different labeling approaches for target-specific biomolecules are summarized. The review comprises a general introduction to the common approaches currently in use, employing the N x S4-x , [3+1] and 2-hydrazino-nicotinicacid (HYNIC) method as well as more recent strategies such as the carbonyl and the TcN approach. Direct labeling without the need of a bifunctional chelator is briefly reviewed as well. More particularly, recent developments in the labeling of concrete targeting molecules, the second generation of radiopharmaceuticals, is then discussed and prominent examples with antibodies/peptides, neuroreceptor targeting small molecules, myocardial imaging agents, vitamins, thymidine, and complexes relevant to multidrug resistance are given. In addition, a new approach toward peptide drug development is described. The section

  5. Applications using high-Tc superconducting terahertz emitters

    NASA Astrophysics Data System (ADS)

    Nakade, Kurama; Kashiwagi, Takanari; Saiwai, Yoshihiko; Minami, Hidetoshi; Yamamoto, Takashi; Klemm, Richard A.; Kadowaki, Kazuo

    2016-03-01

    Using recently-developed THz emitters constructed from single crystals of the high-Tc superconductor Bi2Sr2CaCu2O8+δ, we performed three prototype tests of the devices to demonstrate their unique characteristic properties for various practical applications. The first is a compact and simple transmission type of THz imaging system using a Stirling cryocooler. The second is a high-resolution Michelson interferometer used as a phase-sensitive reflection-type imaging system. The third is a system with precise temperature control to measure the liquid absorption coefficient. The detailed characteristics of these systems are discussed.

  6. Isospin symmetry breaking in 93Tc and statistical properties

    NASA Astrophysics Data System (ADS)

    Åberg, S.; Heine, A.; Mitchell, G. E.; Richter, A.

    2004-09-01

    We present a statistical analysis of proton resonances in the compound nucleus 93Tc in terms of random matrix theory (RMT). The fluctuation properties of energy levels and reduced widths from data measured by Bilpuch et al. [Phys. Rev. C 9 (1974) 1589] are studied. We conclude that one T> = 9 / 2 isobaric analog state does not affect the spectral correlations of a sequence of 124 T< = 7 / 2 states, and that the observed deviations from RMT are due to unobserved levels. For the reduced widths, however, certain deviations from Porter-Thomas statistics are attributed to the effect of isospin mixing.

  7. Tc-99m glucoheptonate is poor man's fluorodeoxyglucose.

    PubMed

    Lele, Ramchandra D

    2011-10-01

    While fluoro-deoxy-glucose (FDG) has emerged as an important radiotracer for imaging tumors, myocardial viability and infection, the role of other glucose analogues should also be explored. Tc-99m Glucoheptonate (GHA) has been used for imaging brain tumors and lung tumors. The uptake mechanism may be linked to GLUT-1 (Glucose transporter) and GLUT-4 expression similar to FDG. GHA is easily available and cheap. With the availability of single photon emission computed tomography/computed tomography (SPECT/CT), GHA imaging should be re-explored as a tumor agent and also for imaging myocardial viability.

  8. Abundances of TC and related elements in stars of type M, MS, and S

    NASA Astrophysics Data System (ADS)

    Vanture, Andrew D.; Wallerstein, George; Brown, Jeffrey A.; Bazan, Grant

    1991-11-01

    Abundances of Co, Zr, Nb, and Tc relative to V have been derived for a sample of ten M and MS stars from 0.10 A/pixel and 0.04 A/pixel Reticon spectra. On a scale with log N(H) = 12.0 and log N(V) = 4.0, it is found that log N(Tc) is about 1.4 for M stars 1.0 MS stars with Tc. It has been suggested by Dominy and Wallerstein that the presence of Tc in M stars which show no enhancements of other s-process elements can be explained by a 'mini s-process'. Detailed calculations and the observed abundances and Tc and related elements presented in this study put this interpretation in doubt. The observations also fail to support the alternative hypothesis suggested by Malaney and Lattanzio that Tc is produced by the photofission of Th and U.

  9. Adhesion reformation: reduction by the use of Interceed (TC7) plus heparin.

    PubMed

    Diamond, M P; Linsky, C B; Cunningham, T; Kamp, L; Pines, E; DeCherney, A H; diZerega, G S

    1991-01-01

    Adhesions frequently develop after surgical procedures. Several groups have demonstrated that reduction of adhesion reformation is more difficult than reduction of adhesion formation. Previous studies have demonstrated the efficacy of Interceed (TC7) (oxidized regenerated cellulose) plus heparin in reducing adhesion formation. Adhesions were created using a previously standardized rabbit uterine horn model. After adhesiolysis, rabbits were assigned randomly to one of four groups: control, Interceed (TC7) alone, Interceed (TC7) plus 500 USP units heparin/horn, and Interceed (TC7) plus 1000 USP units heparin/horn. Adhesion reformation was evaluated 2 weeks later. Combination of the Interceed (TC7) barrier plus heparin resulted in a significant reduction of the adhesion reformation scores. It is concluded that Interceed (TC7) plus heparin is efficacious in reduction of both adhesion formation and adhesion reformation.

  10. Comparative metabolic behavior and interrelationships of Tc and S in soybean plants

    SciTech Connect

    Cataldo, D.A.; Garland, T.R.; Wildung, R.E.; Fellows, R.J. )

    1989-08-01

    The comparative behavior of sulfur (S) and technetium (Tc) in soybean seedlings shows gross subcellular distributions to be similar for these oxyanions. More than 75% of the tissue-deposited Tc remains soluble and extractable. Differences in Tc fixation/incorporation were noted for the nuclear and chloroplast fractions of leaf and root cells. Pulse studies showed that soluble protein and nitrate reductase levels rose in response to Tc accumulation by sink leaves but not source leaves. In vitro assay of chloroplast-based S reduction and incorporation systems showed Tc to be reduced and incorporated into amino nitrogen-containing products. A hypothesis related to the metabolic behavior of Tc in plants is presented.

  11. Power Systems Development Facility Gasification Test Run TC11

    SciTech Connect

    Southern Company Services

    2003-04-30

    This report discusses Test Campaign TC11 of the Kellogg Brown & Root, Inc. (KBR) Transport Gasifier train with a Siemens Westinghouse Power Corporation (Siemens Westinghouse) particle filter system at the Power Systems Development Facility (PSDF) located in Wilsonville, Alabama. The Transport Gasifier is an advanced circulating fluidized-bed gasifier designed to operate as either a combustor or a gasifier in air- or oxygen-blown mode of operation using a particulate control device (PCD). Test run TC11 began on April 7, 2003, with startup of the main air compressor and the lighting of the gasifier start-up burner. The Transport Gasifier operated until April 18, 2003, when a gasifier upset forced the termination of the test run. Over the course of the entire test run, gasifier temperatures varied between 1,650 and 1,800 F at pressures from 160 to 200 psig during air-blown operations and around 135 psig during enriched-air operations. Due to a restriction in the oxygen-fed lower mixing zone (LMZ), the majority of the test run featured air-blown operations.

  12. An Overview of ER-2 Platform Science during TC4

    NASA Astrophysics Data System (ADS)

    Platnick, S.; Newman, P. A.

    2007-12-01

    The NASA high-altitude ER-2 aircraft flew 11 science flight out of San Jose, Costa Rica during July and August 2007 as part of the NASA-sponsored Tropical Composition, Clouds and Climate Coupling Experiment (TC4). The ER-2 flew a remote sensing payload consisting of passive optical and microwave imagers (MAS/MASTER, CoSSIR, AMPR), a high spectral resolution IR imager (S-HIS), active sensors (CPL lidar, CRS and EDOP radars), spectral solar (SSFR) and IR flux radiometers, a microwave temperature profiler (MTP), and a visible video camera (MVIS). This suite of sensors provided a high spatial resolution simulator for cloud, aerosol, sounding, and trace gas retrieval capabilities from the "A-Train" constellation, in particular, the Aqua, CloudSat, and CALIPSO satellites. In this talk we present an overview of the ER-2 TC4 science and validation objectives, and a summary of the campaign accomplishments. Science goals included observations of convective system development, anvil cirrus property evolution (i.e., microphysics, optical properties, narrow and broadband radiative fluxes), tropical Tropopause Transition Layer (TTL) and subvisual cirrus detection and characterization, marine boundary layer cloud properties, aerosol transport and optical properties, and trace gas and atmospheric state characteristics. Coordination with the DC-8 and/or WB-57 aircrafts allowed for validation of various retrievals from these observations. Morning flights (due to adverse local afternoon weather conditions) included coordination with the Terra spacecraft when feasible.

  13. Power Systems Development Facility Gasification Test Campaign TC16

    SciTech Connect

    Southern Company Services

    2004-08-24

    In support of technology development to utilize coal for efficient, affordable, and environmentally clean power generation, the Power Systems Development Facility (PSDF) located in Wilsonville, Alabama, routinely demonstrates gasification technologies using various types of coals. The PSDF is an engineering scale demonstration of key features of advanced coal-fired power systems, including a KBR (formerly Kellogg Brown & Root) Transport Gasifier, a hot gas particulate control device, advanced syngas cleanup systems, and high-pressure solids handling systems. This report discusses Test Campaign TC16 of the PSDF gasification process. TC16 began on July 14, 2004, lasting until August 24, 2004, for a total of 835 hours of gasification operation. The test campaign consisted of operation using Powder River Basin (PRB) subbituminous coal and high sodium lignite from the North Dakota Freedom mine. The highest gasifier operating temperature mostly varied from 1,760 to 1,850 F with PRB and 1,500 to 1,600 F with lignite. Typically, during PRB operations, the gasifier exit pressure was maintained between 215 and 225 psig using air as the gasification oxidant and between 145 and 190 psig while using oxygen as the oxidant. With lignite, the gasifier operated only in air-blown mode, and the gasifier outlet pressure ranged from 150 to 160 psig.

  14. Power Systems Development Facility Gasification Test Campaign TC22

    SciTech Connect

    Southern Company Services

    2008-11-01

    In support of technology development to utilize coal for efficient, affordable, and environmentally clean power generation, the Power Systems Development Facility (PSDF), located in Wilsonville, Alabama, routinely demonstrates gasification technologies using various types of coals. The PSDF is an engineering scale demonstration of key features of advanced coal-fired power systems, including a KBR Transport Gasifier, a hot gas particulate control device, advanced syngas cleanup systems, and high-pressure solids handling systems. This report summarizes the results of TC22, the first test campaign using a high moisture lignite from Mississippi as the feedstock in the modified Transport Gasifier configuration. TC22 was conducted from March 24 to April 17, 2007. The gasification process was operated for 543 hours, increasing the total gasification operation at the PSDF to over 10,000 hours. The PSDF gasification process was operated in air-blown mode with a total of about 1,080 tons of coal. Coal feeder operation was challenging due to the high as-received moisture content of the lignite, but adjustments to the feeder operating parameters reduced the frequency of coal feeder trips. Gasifier operation was stable, and carbon conversions as high as 98.9 percent were demonstrated. Operation of the PCD and other support equipment such as the recycle gas compressor and ash removal systems operated reliably.

  15. Tc-99m MDP, thallium-201 chloride and Tc-99m MAG3 renal uptake in subacute and chronic radiation nephritis compared.

    PubMed

    Degirmenci, B; Uysal, K; Bekis, R; Cetingoz, R; Kaya, G C; Durak, H

    2001-10-01

    The authors present a comparison of the findings for thallium-201 (Tl-201), Tc-99m MAG3 and Tc-99m MDP in subacute and chronic radiation nephritis in a 9-yr-old boy who was treated by radiation therapy for alveolar rhabdomyosarcoma of the left chest wall by a radiation port that partially included the left kidney. Tl-201 imaging three and six months later showed a cortical defect in the left kidney due to radiation nephritis. Tc-99m MDP scan showed increased uptake on both occasions, but more marked in the subacute period than in the chronic period. Tc-99m MAG3 showed decreased concentration and increased cortical retention three months later. Six months after the radiation therapy, a cortical defect corresponding to the cortical area that showed increased parenchymal retention was more prominent in the Tc-99m MAG3 scan. In the present case, Tc-99m MDP, Tl-201 and Tc-99m MAG3 findings may provide useful information for understanding pathophysiological damage in the kidney after radiation.

  16. Tumor-specific IL-9-producing CD8+ Tc9 cells are superior effector than type-I cytotoxic Tc1 cells for adoptive immunotherapy of cancers.

    PubMed

    Lu, Yong; Hong, Bangxing; Li, Haiyan; Zheng, Yuhuan; Zhang, Mingjun; Wang, Siqing; Qian, Jianfei; Yi, Qing

    2014-02-11

    Because cytokine-priming signals direct CD8(+) T cells to acquire unique profiles that affect their ability to mediate specific immune responses, here we generated IL-9-skewed CD8(+) T (Tc9) cells by priming with Th9-polarized condition. Compared with type-I CD8(+) cytotoxic T (Tc1) cells, Tc9 secreted different cytokines and were less cytolytic in vitro but surprisingly elicited greater antitumor responses against advanced tumors in OT-I/B16-OVA and Pmel-1/B16 melanoma models. After adoptive transfer, Tc9 cells persisted longer and differentiated into IFN-γ- and granzyme-B (GrzB)-producing cytolytic Tc1-like effector cells. Phenotypic analysis revealed that adoptively transferred Tc9 cells secreted IL-2 and were KLRG-1(low) and IL-7Rα(high), suggesting that they acquired a signature of "younger" phenotype or became long-term lived cells with capacity of self-renewal. Our results also revealed that Tc9-mediated therapeutic effect critically depended on IL-9 production in vivo. These findings have clinical implications for the improvement of CD8(+) T-cell-based adoptive immunotherapy of cancers.

  17. Unpredicted phenotypes of two mutants of the TcR DMF5.

    PubMed

    Tadesse, Fitsum G; Mensali, Nadia; Fallang, Lars-Egil; Walseng, Even; Yang, Weiwen; Olweus, Johanna; Wälchli, Sébastien

    2015-10-01

    When a T-cell Receptor (TcR) interacts with its cognate peptide-MHC (pMHC), it triggers activation of a signaling cascade that results in the elicitation of a T cell effector function. Different models have been proposed to understand which parameters are needed to obtain an optimal activation of the signaling. It was speculated that improving the binding of a TcR could bring a stronger pMHC recognition, hence a stronger stimulation of the T cell. However, it was recently shown that an increase in affinity does not seem to be sufficient to guarantee improved functionality. A combination of factors is necessary to place the modified TcR in an optimal functional window. We here compared the binding parameters of two mutants of the melanoma antigen peptide MART-127-35 specific TcR DMF5. The first mutant was previously isolated by others in a screen for improved TcR. It was reported to have an increased CD8-independent activity. We confirmed these data and showed that the enhancement was neither due to change in half life (t1/2) nor Kd of the pMHC-TcR complex. The second mutant was designed based on a previous report claiming that a particular polymorphic residue in the TRAV12-2 chain was stabilizing the TcR. We created a DMF5 mutant for this residue and showed that, unexpectedly, this TcR had acquired a reduced overall activity although the TcR-pMHC complex was more stable when compared to the TcR wild type complex (increased t1/2). In addition, the soluble TcR form of this mutant bound target cells less efficiently. From this we concluded that kinetic parameters do not always predict the superior functionality of mutant TcRs.

  18. First 13 years of high-{Tc}: Brief review and open questions

    SciTech Connect

    Pavuna, D.

    1999-12-20

    Exactly 13 years ago, in April 1986, appeared the famous paper by Bednorz and Mueller, that announced a striking discovery of high-{Tc} superconductivity in cuprates. Some 40,000 papers later, scientists are still struggling to understand the high-{Tc} superconductivity. Here the author summarizes some of the most relevant recent results and open questions by discussing the observed phenomena in a rather complex electronic phase diagram of high-{Tc} oxides.

  19. Tc-99m DTPA uptake in extramedullary plasmacytoma of the retroperitoneum

    SciTech Connect

    Aburano, T.; Yokoyama, K.; Michigishi, T.; Tonami, N.; Hisada, K.

    1988-12-01

    A case is presented in which uptake of Tc-99m DTPA has been demonstrated in an extramedullary plasmacytoma of the retroperitoneum. Because Ga-67 citrate does not concentrate in the same areas as Tc-99m DTPA, a radionuclide-specific uptake mechanism may be present. Extramedullary plasmacytoma should be included in the list of possible causes if extrarenal or extracentral nervous system uptake of Tc-99m DTPA occurs.

  20. Tc-99m hexamethylpropylene-amine oxine (HM-PAO) uptake in a bone metastasis

    SciTech Connect

    Hoshi, H.; Jinnouchi, S.; Sameshima, M.; Uwada, O.; Watanabe, K.

    1988-08-01

    Uptake of Tc-99m Hexamethylpropylene-amine Oxine (HM-PAO) was seen in bone metastases from carcinoma of the lung. The uptake was prominent when compared to Tc-99m MDP, I-123 IMP, and Ga-67 citrate. Brain imaging with Tc-99m HM-PAO and N-isopropyl-p-(I-123) iodoamphetamine (IMP) is now frequently performed. Uptake of these agents has been reported in brain tumors and melanomas. In this report, uptake of Tc-99m HM-PAO in a metastatic lesion in bone is discussed.

  1. Impeding 99Tc(IV) mobility in novel waste forms

    SciTech Connect

    Lee, Mal-Soon; Um, Wooyong; Wang, Guohui; Kruger, Albert A.; Lukens, Wayne W.; Rousseau, Roger; Glezakou, Vassiliki-Alexandra

    2016-06-30

    Technetium (99Tc) is a long-lived radioactive fission product whose mobility in the subsurface is largely governed by its oxidation state1. Immobilization of Tc in mineral substrates is crucial for radioactive waste management and environmental remediation. Tc(IV) incorporation in spinels2, 3 has been proposed as a novel method to increase Tc retention in glass waste forms. However, experiments with Tc-magnetite under high temperature and oxic conditions showed re-oxidation of Tc(IV) to volatile pertechnetate Tc(VII)O4-.4, 5 Here we address this problem with large-scale ab initio molecular dynamics simulations and propose that elevated temperatures, 1st row transition metal dopants can significantly enhance Tc retention in the order Co > Zn > Ni. Experiments with doped spinels at T=700 ºC provided quantitative confirmation of increased Tc retention in the same order predicted by theory. This work highlights the power of modern state-of-the-art simulations to provide essential insights and generate bottom-up design criteria of complex oxide materials at elevated temperatures.

  2. Pentachlorooxotechnetate(VI) anion, (TcOCl/sub 5/): an EPR study

    SciTech Connect

    Kirmse, R.; Stach, J.; Abram, U.

    1985-07-03

    The anion pentachlorooxotechnetate(VI), TcOCl/sub 5//sup -/, has been prepared by reduction of TcO/sub 4//sup -/ with HCl in concentrated H/sub 2/SO/sub 4/ and investigated by means of the EPR technique. The axial symmetric spectrum suggests an in-plane ..pi..-type ground state of the MO of the unpaired electron. The Tc-Cl/sub eq/ bonding properties have been discussed in terms of MO theory, and a comparison has been given to the bonding properties in likely complexes of neighboring elements of Tc.

  3. Congenital renal anomaly: evaluation with 99mTc-dimercaptosuccinic acid renal scintigraphy.

    PubMed

    Hosokawa, S; Kawamura, J; Tomoyoshi, T; Yoshida, O

    1983-05-01

    Technetium 99m-2,3, dimercaptosuccinic acid (99mTc-DMSA) preferentially accumulates in the renal cortex, demonstrating functioning cortical mass. We used 99mTc-DMSA renal scintigraphy in ten patients with horseshoe kidneys and five patients with unilateral fused kidneys. The results show that 99mTc-DMSA renal scintigraphy reliably establishes the diagnosis of horseshoe kidney and clearly shows the isthmus, which is very essential for proper management. The technique also aids in the definitive assessment of separate kidney function and of total radionuclide uptake is possible using 99mTc-DMSA scintigraphy.

  4. Leaching TC-99 from DWPF glass in simulated geologic repository groundwaters

    SciTech Connect

    Bibler, N.E.; Jurgensen, A.R.

    1986-09-30

    The purpose was to determine if DWPF glass in geologic groundwaters would immobilize Tc-99 as well as it does other elements. A previous study (using a borosilicate glass of a very different composition from DWPF glass) indicated that Tc-99 leached rapidly from the glass suggesting that glass may not be a good matrix for immobilizing Tc-99. It was suggested that the Tc-99 had migrated to vesicles in the glass while the glass was still molten. To determine if borosilicate glass was a good immobilizing matrix for Tc-99, this study was performed using DWPF glass. The leaching of Tc-99 was compared to other elements in the glass. It was shown that rapid leaching will not occur with SRP glass. The leach rate for Tc-99 was nearly identical to that for B, a matrix element in the glass. Another objective was to compare the release of Tc-99 under oxidizing and reducing conditions with other elements in the glass. In the tests described here, even though the glass was dissolving more under reducing conditions as a result of abnormally high pH values, less Tc-99 appeared in solution.

  5. Accumulation of 99mTc-PMT in renal metastasis of hepatocellular carcinoma.

    PubMed

    Shiozaki, Toshiki; Hayakawa, Katsumi; Tanikake, Masato; Oida, Tomoyuki; Hida, Shuichi; Yasui, Hiroshi; Urata, Yoji; Tanaka, Akira; Morimoto, Taisuke

    2003-06-01

    We describe here a case in which 99mTc-Sn-N-pyridoxy-5-methyltryptophan (99mTc-PMT) scintigraphy was useful in diagnosing renal metastasis of hepatocellular carcinoma (HCC). A 62-year-old man who had undergone hepatectomy for HCC presented 6 years after initial diagnosis with left flank pain and was found on CT and MRI to have a tumor in the left kidney. Hepatobiliary scintigraphy using 99Tc-PMT was performed, and 99mTc-PMT accumulation was found in the tumor. Nephrectomy was performed and metastasis of HCC was confirmed.

  6. Congenital renal anomaly: evaluation with 99mTc-dimercaptosuccinic acid renal scintigraphy

    SciTech Connect

    Hosokawa, S.; Kawamura, J.; Tomoyoshi, T.; Yoshida, O.

    1983-05-01

    Technetium 99m-2,3, dimercaptosuccinic acid (99mTc-DMSA) preferentially accumulates in the renal cortex, demonstrating functioning cortical mass. We used 99mTc-DMSA renal scintigraphy in ten patients with horseshoe kidneys and five patients with unilateral fused kidneys. The results show that 99mTc-DMSA renal scintigraphy reliably establishes the diagnosis of horseshoe kidney and clearly shows the isthmus, which is very essential for proper management. The technique also aids in the definitive assessment of separate kidney function and of total radionuclide uptake is possible using 99mTc-DMSA scintigraphy.

  7. Differential uptake of Tc-99m DMSA and Tc-99m EC in renal tubular disorders: Report of two cases and review of the literature

    PubMed Central

    Reddy Gorla, Arun Kumar; Agrawal, Kanhaiyalal; Sood, Ashwani; Bhattacharya, Anish; Mittal, Bhagwant Rai

    2014-01-01

    Tc-99m DMSA and Tc-99m EC studies are invaluable functional imaging modalities for renal structural and functional assessment. Normally, the relative renal function estimated by the two methods correlates well with each other. We here present two patients with renal tubular acidosis who showed impaired/altered DMSA uptake with normal EC renal dynamic study depicting the pitfall of DMSA imaging in tubular disorders. The two presented cases also depict distinct pattern of Tc-99m DMSA scintigraphic findings in patients with proximal and distal renal tubular acidosis, thus highlighting the factors affecting DMSA kinetics. PMID:25210282

  8. Differential uptake of Tc-99m DMSA and Tc-99m EC in renal tubular disorders: Report of two cases and review of the literature.

    PubMed

    Reddy Gorla, Arun Kumar; Agrawal, Kanhaiyalal; Sood, Ashwani; Bhattacharya, Anish; Mittal, Bhagwant Rai

    2014-07-01

    Tc-99m DMSA and Tc-99m EC studies are invaluable functional imaging modalities for renal structural and functional assessment. Normally, the relative renal function estimated by the two methods correlates well with each other. We here present two patients with renal tubular acidosis who showed impaired/altered DMSA uptake with normal EC renal dynamic study depicting the pitfall of DMSA imaging in tubular disorders. The two presented cases also depict distinct pattern of Tc-99m DMSA scintigraphic findings in patients with proximal and distal renal tubular acidosis, thus highlighting the factors affecting DMSA kinetics.

  9. Magnetic and thermal properties of high Tc superconductors

    SciTech Connect

    Lee, Wonchoon.

    1990-09-21

    Measurements of the normal state magnetic susceptibility {chi}(T) of YBa{sub 2}Cu{sub 3}O{sub 7}, Bi{sub 1.8}Pb{sub 0.2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}}, and Bi{sub 2{minus}x}Pb{sub x}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub 10+{delta}} (x = 0.2 and 0.25) were carried out. All {chi}(T) data show negative curvature below {approximately}2{Tc}. The data for YBa{sub 2}Cu{sub 3}O{sub 7} are in excellent agreement with a new calculation of the superconducting fluctuation diamagnetism. From the analysis, we infer s-wave pairing and microscopic parameters are obtained. For {chi}(T) of YBa{sub 2}Cu{sub 3}O{sub 7}, part of the negative curvature is inferred to arise from the normal state background. We find a strong temperature dependent anisotropy {delta}{chi} {equivalent to} {chi}{sub c} {minus} {chi}{sub ab} and estimate the normal state spin contributions to {chi}(T). The heat capacity C(T) of YBa{sub 2}Cu{sub 3}O{sub 7} is reported for 0.4 K < T < 400 K in zero and 70 kG magnetic fields. In addition to the feature associated with the onset of the superconductivity at {Tc}, two anomalies in C(T) were observed near 74 K and 330 K, with another possible anomaly near 102 K; the temperatures at which they occur correlate with anomalies in {chi}(T) and ultransonic measurements. The occurrence of the anomaly at {approx equal} 330 K is found to be sample-dependent. The influences of a magnetic field and the thermal and/or magnetic field treatment history dependence of a pellet sample on C(T), the entropy and the influence of superconducting fluctuations on C(T) near {Tc}, and the possible source of the observed intrinsic nonzero {gamma}(0) at low T are discussed.

  10. 99mTc-labeled HYNIC-DAPI causes plasmid DNA damage with high efficiency.

    PubMed

    Kotzerke, Joerg; Punzet, Robert; Runge, Roswitha; Ferl, Sandra; Oehme, Liane; Wunderlich, Gerd; Freudenberg, Robert

    2014-01-01

    (99m)Tc is the standard radionuclide used for nuclear medicine imaging. In addition to gamma irradiation, (99m)Tc emits low-energy Auger and conversion electrons that deposit their energy within nanometers of the decay site. To study the potential for DNA damage, direct DNA binding is required. Plasmid DNA enables the investigation of the unprotected interactions between molecules and DNA that result in single-strand breaks (SSBs) or double-strand breaks (DSBs); the resulting DNA fragments can be separated by gel electrophoresis and quantified by fluorescent staining. This study aimed to compare the plasmid DNA damage potential of a (99m)Tc-labeled HYNIC-DAPI compound with that of (99m)Tc pertechnetate ((99m)TcO4(-)). pUC19 plasmid DNA was irradiated for 2 or 24 hours. Direct and radical-induced DNA damage were evaluated in the presence or absence of the radical scavenger DMSO. For both compounds, an increase in applied activity enhanced plasmid DNA damage, which was evidenced by an increase in the open circular and linear DNA fractions and a reduction in the supercoiled DNA fraction. The number of SSBs elicited by 99mTc-HYNIC-DAPI (1.03) was twice that caused by (99m)TcO4(-) (0.51), and the number of DSBs increased fivefold in the (99m)Tc-HYNIC-DAPI-treated sample compared with the (99m)TcO4(-) treated sample (0.02 to 0.10). In the presence of DMSO, the numbers of SSBs and DSBs decreased to 0.03 and 0.00, respectively, in the (99m)TcO4(-) treated samples, whereas the numbers of SSBs and DSBs were slightly reduced to 0.95 and 0.06, respectively, in the (99m)Tc-HYNIC-DAPI-treated samples. These results indicated that (99m)Tc-HYNIC-DAPI induced SSBs and DSBs via a direct interaction of the (99m)Tc-labeled compound with DNA. In contrast to these results, (99m)TcO4(-) induced SSBs via radical formation, and DSBs were formed by two nearby SSBs. The biological effectiveness of (99m)Tc-HYNIC-DAPI increased by approximately 4-fold in terms of inducing SSBs and by

  11. 99mTc-Labeled HYNIC-DAPI Causes Plasmid DNA Damage with High Efficiency

    PubMed Central

    Kotzerke, Joerg; Punzet, Robert; Runge, Roswitha; Ferl, Sandra; Oehme, Liane; Wunderlich, Gerd; Freudenberg, Robert

    2014-01-01

    99mTc is the standard radionuclide used for nuclear medicine imaging. In addition to gamma irradiation, 99mTc emits low-energy Auger and conversion electrons that deposit their energy within nanometers of the decay site. To study the potential for DNA damage, direct DNA binding is required. Plasmid DNA enables the investigation of the unprotected interactions between molecules and DNA that result in single-strand breaks (SSBs) or double-strand breaks (DSBs); the resulting DNA fragments can be separated by gel electrophoresis and quantified by fluorescent staining. This study aimed to compare the plasmid DNA damage potential of a 99mTc-labeled HYNIC-DAPI compound with that of 99mTc pertechnetate (99mTcO4−). pUC19 plasmid DNA was irradiated for 2 or 24 hours. Direct and radical-induced DNA damage were evaluated in the presence or absence of the radical scavenger DMSO. For both compounds, an increase in applied activity enhanced plasmid DNA damage, which was evidenced by an increase in the open circular and linear DNA fractions and a reduction in the supercoiled DNA fraction. The number of SSBs elicited by 99mTc-HYNIC-DAPI (1.03) was twice that caused by 99mTcO4− (0.51), and the number of DSBs increased fivefold in the 99mTc-HYNIC-DAPI-treated sample compared with the 99mTcO4− treated sample (0.02 to 0.10). In the presence of DMSO, the numbers of SSBs and DSBs decreased to 0.03 and 0.00, respectively, in the 99mTcO4– treated samples, whereas the numbers of SSBs and DSBs were slightly reduced to 0.95 and 0.06, respectively, in the 99mTc-HYNIC-DAPI-treated samples. These results indicated that 99mTc-HYNIC-DAPI induced SSBs and DSBs via a direct interaction of the 99mTc-labeled compound with DNA. In contrast to these results, 99mTcO4− induced SSBs via radical formation, and DSBs were formed by two nearby SSBs. The biological effectiveness of 99mTc-HYNIC-DAPI increased by approximately 4-fold in terms of inducing SSBs and by approximately 10-fold in terms of

  12. Differential receptor targeting of liver cells using 99mTc-neoglycosylated human serum albumins.

    PubMed

    Kim, Sungeun; Jeong, Jae Min; Hong, Mee Kyung; Jang, Ja-June; Lee, Jaetae; Lee, Dong Soo; Chung, June-Key; Lee, Myung Chul

    2008-01-01

    Neolactosyl human serum albumin (LSA) targets asialoglycoprotein receptor and shows high liver uptake due to accumulation in hepatocytes. Although neomannosyl human serum albumin (MSA) also shows high liver uptake, it has been reported to be taken up by Kupffer cells and endothelial cells. We compared the biological properties of LSA and MSA. 99mTc-LSA and 99mTc-MSA biodistribution in mice were investigated after intravenous injection. In vivo localization of rhodaminisothiocyanate (RITC)-LSA and fluoresceineisothiocyanate (FITC)-MSA were investigated in mouse liver. Excretion routes of 99mTc-LSA and 99mTc-MSA metabolites were examined. Both 99mTc-LSA and 99mTc-MSA showed high liver uptakes. RITC-LSA was taken up by hepatocytes whereas FITC-MSA was taken up by Kupffer cells and endothelial cells. 99mTc-MSA showed higher spleen and kidney uptakes than 99mTc-LSA. 99mTc-LSA metabolites excreted in urine and feces accounted for 44.4 and 50.0% of 99mTc-LSA injected, respectively, while 99mTc-MSA metabolites accounted for 51.5 and 10.3%, respectively. In conclusion, LSA is specifically taken up by hepatcytes while MSA by Kupffer cells and endothelial cells. After taken up by the liver, LSA is metabolized by the hepatocytes and then excreted through both the hepatobiliary tract and kidney, whereas MSA is metabolized by Kupffer cells and endoghelial cells and then excreted mainly through the kidney.

  13. Radiation-dosimetry and chemical-toxicity considerations for /sup 99/Tc

    SciTech Connect

    Coffey, J.L.; Hayes, R.L.; Rafter, J.J.; Watson, E.E.; Carlton, J.E.

    1982-01-01

    Technetium-99 (T/sub 1/2/ = 2.13 x 10/sup 5/ y) is produced in the fission of /sup 235/U and /sup 239/Pu. Technitium-99 has been found to contaminate some areas of the uranium re-enrichment process. ICRP-30 Part 2 gives the Annual Limit on Intake (ALI) for /sup 99/Tc as 2 x 10/sup 8/ Bq (5.4 mCi) for class D inhaled material (IC80). The ICRP states clearly that ALIs are based on radiation risk only and that chemical toxicity is not considered (IC79). No data wer found on the chemical toxicity of /sup 99/Tc, possibly because there are no stable isotopes of technetium with which to study the toxicity, although, because of its long T/sub 1/2/, /sup 99/Tc can, for all practical purposes, be considered stable. The ALI values for /sup 99/Tc are based on data obtained using high specific activity /sup 99m/Tc (T/sub 1/2/ = 6 h) and /sup 95m/Tc (T/sub 1/2/ = 61 days). Since the specific activities of /sup 99/Tc and Na/sup 99/TcO/sub 4/ are quite low (17 mCi/g and 9 mCi/g, respectively) and /sup 99/Tc is available in abundant supply, we have attempted to assess the relative radiation and chemical hazards that are associated with this radionuclide. The approach in this study was (1) to study the effect of chemical dose on the whole body retention of /sup 99/Tc sodium pertechnetate in rats and to relate these effects to the radiation dose and the ALI and (2) to compare the chemical toxicity of /sup 99/Tc sodium pertechnetate with the ALI at different chemical dose levels.

  14. Synthesis, structure elucidation and redox properties of 99Tc complexes of lacunary Wells Dawson polyoxometalates: insights into molecular 99Tc - metal oxide interactions

    SciTech Connect

    McGregor, Donna; Burton-Pye, Benjamin P.; Howell, Robertha C.; Mbomekalle, Israel M.; Lukens Jr, Wayne W.; Bian, Fang; Mausolf, Edward; Poineau, Frederic; Czerwinski, Kenneth R; Francesconi, Lynn C.

    2011-01-10

    The isotope 99Tc (beta max: 250 keV, half-life: 2 x 105 year) is an abundant product of uranium-235 fission in nuclear reactors and is present throughout the radioactive waste stored in underground tanks at Hanford and Savannah River. Understanding and controlling the extensive redox chemistry of 99Tc is important to identify tunable strategies to separate 99Tc from spent fuel and from waste tanks and once separated, to identify and develop an appropriately stable waste-form for 99Tc. Polyoxometalates (POMs), nanometer sized models for metal oxide solid-state materials, are used in this study to provide a molecular level understanding of the speciation and redox chemistry of incorporated 99Tc. In this study, 99Tc complexes of the (alpha 2-P2W17O61)10- and (alpha 1-P2W17O61)10- isomers were prepared. Ethylene glycol was used as a"transfer ligand" to minimize the formation of TcO2 cdot xH2O. The solution structures, formulations, and purity of TcVO(alpha 1/alpha 2-P2W17O61)7- were determined by multinuclear NMR. X-ray Absorption Spectroscopy of the complexes are in agreement with the formulation and structures determined from 31P and 183W NMR. Preliminary electrochemistry results are consistent with the EXAFS results, showing a facile reduction of the TcVO(alpha 1-P2W17O61)7- species compared to the TcVO(alpha 2-P2W17O61)7- analog. The alpha1- defect is unique in that a basic oxygen atom is positioned toward the alpha1- site and the TcVO center appears to form a dative metal-metal bond with a framework W site. These attributes may lead to the assistance of protonation events that facilitate reduction. Electrochemistry comparison shows that the ReV analogs are about 200 mV more difficult to reduce in accordance with periodic trends.

  15. Resident aliens: the Tc1/mariner superfamily of transposable elements.

    PubMed

    Plasterk, R H; Izsvák, Z; Ivics, Z

    1999-08-01

    Transgenic technology is currently applied to several animal species of agricultural or medical importance, such as fish, cattle, mosquitos and parasitic worms. However, the repertoire of genetic tools used for molecular analyses of mice and Drosophila is not always applicable to other species. For example, while retroviral enhancer-trap experiments in mice can be based on embryonic stem (ES) cell technology, this is not currently an option with other animals. Similarly, the germline transformation of Drosophila depends on the use of the P-element transposon, which does not jump in other genera. This article analyses the main characteristics of Tc1/mariner transposable elements, examines some of the factors that have contributed to their evolutionary success, and describes their potential, as well as their limitations, for transgenesis and insertional mutagenesis in diverse animals.

  16. The first five years of high- Tc superconductivity

    NASA Astrophysics Data System (ADS)

    Müller, K. Alex

    1991-12-01

    After the 1986 discovery and confirmation of superconductivity in doped La 2CuO 4, a “gold rush” occurred in the following year when the transition temperature in YBa 2Cu 3O 7-δ exceeded the boiling point of liquid nitrogen. In 1988, even higher Tc's were reported in new compounds without rare-earth ions. The preparation techniques started to be improved substantially and results on scholarly conducted experiments became available. Since then, the data obtained with different techniques fitted together like pieces of a puzzle, and continue to do so. Early in 1987, high critical magnetic fields and currents were reported in epitaxial films and single crystals. This opened the way for application-oriented research and has led to first true successes in 1990/91. The following is a near verbal transcript of my presentation.

  17. Theory of high Tc ferrimagnetism in a multiorbital Mott insulator.

    PubMed

    Meetei, O Nganba; Erten, Onur; Randeria, Mohit; Trivedi, Nandini; Woodward, Patrick

    2013-02-22

    We propose a model for the multiorbital material Sr(2)CrOsO(6), an insulator with remarkable magnetic properties and the highest T(c) ~/= 725 K among all perovskites with a net moment. We derive a new criterion for the Mott transition (U(1)U(2))(1/2)>2.5W by using slave-rotor mean field theory, where W is the bandwidth and U(1(2)) are the effective Coulomb interactions on Cr(Os) including Hund's coupling. We show that Sr(2)CrOsO(6) is a Mott insulator, where the large Cr U(1) compensates for the small Os U(2). The spin sector is described by a frustrated antiferromagnetic Heisenberg model that naturally explains the net moment arising from canting and also the observed nonmonotonic magnetization M(T). We predict characteristic magnetic structure factor peaks that can be probed by neutron experiments.

  18. In-Situ Data for Microphysical Retrievals: TC4, 2007

    DOE Data Explorer

    Mace, Gerald

    2016-04-01

    This data set is derived from measurements collected in situ by the NASA DC8 during the Tropical Cloud Climate Composition Coupling Experiment (TC4) that was conducted during July and August, 2007 (Toon et al., 2010). During this experiment the DC8 was based in San Jose, Costa Rica and sampled clouds in the maritime region of the Eastern Pacific and adjoining continental areas. The primary objective of the DC8 during this deployment was to sample ice clouds associated with convective activity. While the vast majority of the data are from ice-phase clouds that have recent association with convection, other types of clouds such as boundary layer clouds and active convection were also sampled and are represented in this data set. The derived data set, as compiled in this delivery, includes approximately 15,000 5-second averaged measurements collected by the NASA DC8.

  19. Buffer layers for high-Tc thin films on sapphire

    NASA Technical Reports Server (NTRS)

    Wu, X. D.; Foltyn, S. R.; Muenchausen, R. E.; Cooke, D. W.; Pique, A.; Kalokitis, D.; Pendrick, V.; Belohoubek, E.

    1992-01-01

    Buffer layers of various oxides including CeO2 and yttrium-stabilized zirconia (YSZ) have been deposited on R-plane sapphire. The orientation and crystallinity of the layers were optimized to promote epitaxial growth of YBa2Cu3O(7-delta) (YBCO) thin films. An ion beam channeling minimum yield of about 3 percent was obtained in the CeO2 layer on sapphire, indicating excellent crystallinity of the buffer layer. Among the buffer materials used, CeO2 was found to be the best one for YBCO thin films on R-plane sapphire. High Tc and Jc were obtained in YBCO thin films on sapphire with buffer layers. Surface resistances of the YBCO films were about 4 mOmega at 77 K and 25 GHz.

  20. Evolution and Exploration of Asteroid 2008 TC3

    NASA Astrophysics Data System (ADS)

    Jenniskens, P. M.; Shaddad, M. H.; Almahata Sitta Consortium

    2011-12-01

    We will discuss ongoing work to fully explore the diversity of materials contained in asteroid 2008 TC3, the small 4-m sized asteroid that was observed in space before hitting Earth on October 7, 2008. A small part of the asteroid was recovered in the form of the Almahata Sitta meteorites two months later. The recovered meteorites were mostly ureilites, but very unexpectedly 20-30 percent of other meteorite types were also recovered. Those included enstatite and ordinary chondrites that became part of the Ureilite Parent Body's daughter asteroids during the evolutionary pathway from the terrestrial region to the asteroid belt. An update will be given on ongoing and projected research into the Almahata Sitta strewnfield and the analysis of the individual meteorites by members of the Almahata Sitta consortium.

  1. Doping dependence of fluctuation diamagnetism in high Tc superconductors

    NASA Astrophysics Data System (ADS)

    Sarkar, Kingshuk; Banerjee, Sumilan; Mukerjee, Subroto; Ramakrishnan, T. V.

    2016-02-01

    Using a recently proposed Ginzburg-Landau-like lattice free energy functional due to Banerjee et al. (2011) we calculate the fluctuation diamagnetism of high-Tc superconductors as a function of doping, magnetic field and temperature. We analyse the pairing fluctuations above the superconducting transition temperature in the cuprates, ranging from the strong phase fluctuation dominated underdoped limit to the more conventional amplitude fluctuation dominated overdoped regime. We show that a model where the pairing scale increases and the superfluid density decreases with underdoping produces features of the observed magnetization in the pseudogap region, in good qualitative and reasonable quantitative agreement with the experimental data. In particular, we explicitly show that even when the pseudogap has a pairing origin the magnetization actually tracks the superconducting dome instead of the pseudogap temperature, as seen in experiment. We discuss the doping dependence of the 'onset' temperature for fluctuation diamagnetism and comment on the role of vortex core-energy in our model.

  2. Evaluation of residual functional lung volume on Tc-99m DTPA aerosol ventilation and Tc-99m MAA perfusion scintigraphy in primary ciliary dyskinesia (Kartagener syndrome).

    PubMed

    Chen, Yu-Wen; Chang, Chin-Chuan; Lai, Yung-Chuang; Lu, Chia-Ying; Dai, Zen-Kong

    2008-12-01

    Kartagener syndrome is diagnosed as sinusitis, bronchitis (bronchiectasis), and situs inversus by the clinical features. It is a subclass of primary ciliary dyskinesia (PCD) disease. A 12-year-old girl who had frequent upper and lower airway infections since birth, which was confirmed as Kartagener syndrome by HRCT imaging. We present the residual functional lung volume and mucociliary clearance findings seen on Tc-99m DTPA aerosol ventilation and Tc-99m MAA perfusion scintigraphy.

  3. TcCYPR04, a Cacao Papain-Like Cysteine-Protease Detected in Senescent and Necrotic Tissues Interacts with a Cystatin TcCYS4.

    PubMed

    Cardoso, Thyago Hermylly Santana; Freitas, Ana Camila Oliveira; Andrade, Bruno Silva; Sousa, Aurizangela Oliveira de; Santiago, André da Silva; Koop, Daniela Martins; Gramacho, Karina Peres; Alvim, Fátima Cerqueira; Micheli, Fabienne; Pirovani, Carlos Priminho

    2015-01-01

    The interaction amongst papain-like cysteine-proteases (PLCP) and their substrates and inhibitors, such as cystatins, can be perceived as part of the molecular battlefield in plant-pathogen interaction. In cacao, four cystatins were identified and characterized by our group. We identified 448 proteases in cacao genome, whereof 134 were cysteine-proteases. We expressed in Escherichia coli a PLCP from cacao, named TcCYSPR04. Immunoblottings with anti-TcCYSPR04 exhibited protein increases during leaf development. Additional isoforms of TcCYSPR04 appeared in senescent leaves and cacao tissues infected by Moniliophthora perniciosa during the transition from the biotrophic to the saprophytic phase. TcCYSPR04 was induced in the apoplastic fluid of Catongo and TSH1188 cacao genotypes, susceptible and resistant to M. perniciosa, respectively, but greater intensity and additional isoforms were observed in TSH1188. The fungal protein MpNEP induced PLCP isoform expression in tobacco leaves, according to the cross reaction with anti-TcCYSPR04. Several protein isoforms were detected at 72 hours after treatment with MpNEP. We captured an active PLCP from cacao tissues, using a recombinant cacao cystatin immobilized in CNBr-Sepharose. Mass spectrometry showed that this protein corresponds to TcCYSPR04. A homology modeling was obtained for both proteins. In order to become active, TcCYSPR04 needs to lose its inhibitory domain. Molecular docking showed the physical-chemical complementarities of the interaction between the cacao enzyme and its inhibitor. We propose that TcCYSPR04 and its interactions with cacao cystatins are involved in the senescence and necrosis events related to witches' broom symptoms. This molecular interaction may be the target for future interventions to control witches' broom disease.

  4. Development of a Luminex Bead Based Assay for Diagnosis of Toxocariasis Using Recombinant Antigens Tc-CTL-1 and Tc-TES-26.

    PubMed

    Anderson, John P; Rascoe, Lisa N; Levert, Keith; Chastain, Holly M; Reed, Matthew S; Rivera, Hilda N; McAuliffe, Isabel; Zhan, Bin; Wiegand, Ryan E; Hotez, Peter J; Wilkins, Patricia P; Pohl, Jan; Handali, Sukwan

    2015-01-01

    The clinical spectrum of human disease caused by the roundworms Toxocara canis and Toxocara cati ranges from visceral and ocular larva migrans to covert toxocariasis. The parasite is not typically recovered in affected tissues, so detection of parasite-specific antibodies is usually necessary for establishing a diagnosis. The most reliable immunodiagnostic methods use the Toxocara excretory-secretory antigens (TES-Ag) in ELISA formats to detect Toxocara-specific antibodies. To eliminate the need for native parasite materials, we identified and purified immunodiagnostic antigens using 2D gel electrophoresis followed by electrospray ionization mass spectrometry. Three predominant immunoreactive proteins were found in the TES; all three had been previously described in the literature: Tc-CTL-1, Tc-TES-26, and Tc-MUC-3. We generated Escherichia coli expressed recombinant proteins for evaluation in Luminex based immunoassays. We were unable to produce a functional assay with the Tc-MUC-3 recombinant protein. Tc-CTL-1 and Tc-TES-26 were successfully coupled and tested using defined serum batteries. The use of both proteins together generated better results than if the proteins were used individually. The sensitivity and specificity of the assay for detecting visceral larval migrans using Tc-CTL-1 plus Tc-TES-26 was 99% and 94%, respectively; the sensitivity for detecting ocular larval migrans was 64%. The combined performance of the new assay was superior to the currently available EIA and could potentially be employed to replace current assays that rely on native TES-Ag.

  5. TcCYPR04, a Cacao Papain-Like Cysteine-Protease Detected in Senescent and Necrotic Tissues Interacts with a Cystatin TcCYS4

    PubMed Central

    Cardoso, Thyago Hermylly Santana; Freitas, Ana Camila Oliveira; Andrade, Bruno Silva; de Sousa, Aurizangela Oliveira; Santiago, André da Silva; Koop, Daniela Martins; Gramacho, Karina Peres; Alvim, Fátima Cerqueira; Micheli, Fabienne; Pirovani, Carlos Priminho

    2015-01-01

    The interaction amongst papain-like cysteine-proteases (PLCP) and their substrates and inhibitors, such as cystatins, can be perceived as part of the molecular battlefield in plant-pathogen interaction. In cacao, four cystatins were identified and characterized by our group. We identified 448 proteases in cacao genome, whereof 134 were cysteine-proteases. We expressed in Escherichia coli a PLCP from cacao, named TcCYSPR04. Immunoblottings with anti-TcCYSPR04 exhibited protein increases during leaf development. Additional isoforms of TcCYSPR04 appeared in senescent leaves and cacao tissues infected by Moniliophthora perniciosa during the transition from the biotrophic to the saprophytic phase. TcCYSPR04 was induced in the apoplastic fluid of Catongo and TSH1188 cacao genotypes, susceptible and resistant to M. perniciosa, respectively, but greater intensity and additional isoforms were observed in TSH1188. The fungal protein MpNEP induced PLCP isoform expression in tobacco leaves, according to the cross reaction with anti-TcCYSPR04. Several protein isoforms were detected at 72 hours after treatment with MpNEP. We captured an active PLCP from cacao tissues, using a recombinant cacao cystatin immobilized in CNBr-Sepharose. Mass spectrometry showed that this protein corresponds to TcCYSPR04. A homology modeling was obtained for both proteins. In order to become active, TcCYSPR04 needs to lose its inhibitory domain. Molecular docking showed the physical-chemical complementarities of the interaction between the cacao enzyme and its inhibitor. We propose that TcCYSPR04 and its interactions with cacao cystatins are involved in the senescence and necrosis events related to witches’ broom symptoms. This molecular interaction may be the target for future interventions to control witches' broom disease. PMID:26641247

  6. The recovery of asteroid 2008 TC[subscript 3

    SciTech Connect

    Shaddad, Muawia H.; Jenniskens, Peter; Numan, Diyaa; Kudoda, Ayman M.; Elsir, Saadia; Riyad, Ihab F.; Ali, Awad Elkareem; Alameen, Mohammed; Alameen, Nada M.; Eid, Omer; Osman, Ahmed T.; AbuBaker, Mohamed I.; Yousif, Mohamed; Chesley, Steven R.; Chodas, Paul W.; Albers, Jim; Edwards, Wayne N.; Brown, Peter G.; Kuiper, Jacob; Friedrich, Jon M.

    2011-09-06

    On October 7, 2008, asteroid 2008 TC{sub 3} impacted Earth and fragmented at 37 km altitude above the Nubian Desert in northern Sudan. The area surrounding the asteroid's approach path was searched, resulting in the first recovery of meteorites from an asteroid observed in space. This was also the first recovery of remains from a fragile 'cometary' PE = IIIa/b type fireball. In subsequent searches, over 600 mostly small 0.2-379 g meteorites (named 'Almahata Sitta') with a total mass 10.7 kg were recovered from a 30 x 7 km area. Meteorites fell along the track at 1.3 kg km{sup -1}, nearly independent of mass between 1 and 400 g, with a total fallen mass of 39 {+-} 6 kg. The strewn field was shifted nearly 1.8 km south from the calculated approach path. The influence of winds on the distribution of the meteorites, and on the motion of the dust train, is investigated. The majority of meteorites are ureilites with densities around 2.8 g cm{sup -3}, some of an anomalous (porous, high in carbon) polymict ureilite variety with densities as low as 1.5 g cm{sup -3}. In addition, an estimated 20-30% (in mass) of recovered meteorites were ordinary, enstatite, and carbonaceous chondrites. Their fresh look and matching distribution of fragments in the strewn field imply that they were part of 2008 TC{sub 3}. For that reason, they are all referred to as 'Almahata Sitta.' No ureilite meteorites were found that still held foreign clasts, suggesting that the asteroid's clasts were only loosely bound.

  7. [Tc1-mediated contact sensitivity reaction, its mechanism and regulation].

    PubMed

    Zemelka-Wiącek, Magdalena; Szczepanik, Marian

    2014-07-04

    The contact hypersensitivity reaction (CHS) to haptens is a classic example of cell-mediated immune response. In the effector phase, two stages can be distinguished: an early component, that appears only 2 hours after subsequent contact with the hapten, and the late component that develops approximately 24 hours later which is mediated by TCRαβ+ cells. The effector lymphocytes may be CD4+ T helper 1 (Th1) cells or CD8+ T cytotoxic 1 (Tc1) cells, which depends on the employed hapten and/or mice strain. NKT lymphocytes play the crucial role in the CHS initiation, by supporting B1 cells in the antigen-specific IgM antibodies production. The development of an early component is essential for the recruitment of T effector (Teff) cells to the side of hapten deposition and for the complete expansion of inflammatory reaction. The CHS reaction is under T regulatory (Treg) cells control, both in the induction phase as well as in the effector phase. A new view of a negative regulation of the Tc1 mediated CHS response is based on the suppression induced by epicutaneous (EC) application of protein antigen. The DNP-BSA skin application, on a gauze patch, leads to a state of immunosuppression. This maneuver results in rising the population of Treg cells with TCRαβ+CD4+CD25+Foxp3+ phenotype. The mechanism of suppression requires direct contact between Treg cells and Teff cells and the participation of CTLA-4 molecule is also necessary. The described method of evoking immune tolerance via EC immunization may contribute to elaborate a new method of allergic contact dermatitis therapy. This is because of its effectiveness, ease of induction and non-invasive protein antigen application.

  8. Moderately shielded high-Tc SQUID system for rat MCG

    NASA Astrophysics Data System (ADS)

    Bechstein, S.; Kim, I.-S.; Drung, D.; Novikov, I.; Schurig, Th

    2010-06-01

    Recently, we have developed a 5-channel high-Tc SQUID system with one signal channel intended for rat magnetocardiography (MCG) in moderately shielded or "quiet" real environment. This system is an adapted version of a human MCG system which has been improved with respect to user-friendliness and stability. A dewar with a cold-warm distance of 7 mm and a refill cycle time of up to one week is utilized. The implemented high-Tc SQUIDs are single-layer devices with grain boundary junctions fabricated at KRISS with laser ablation on 10 mm × 10 mm STO substrates. In order to cancel environmental magnetic noise, three of the five SQUIDs are arranged to build an axial software first-order or second-order gradiometer with a base line of 35 mm. The other two SQUIDs are used for balancing. To overcome previous system instabilities, we have implemented an Earth field compensation for each SQUID. For this, the SQUIDs were mounted in capsules containing integrated field compensation coils. The three Earth field components are measured with an additional triaxial fluxgate, and compensated at the SQUID locations using the low-noise current source of the SQUID readout electronics. This way, the SQUIDs can be cooled and operated in a low residual field that improves system stability and reduces low-frequency SQUID noise. It is even possible to slowly move the dewar in the Earth field (dynamic field compensation). Different noise cancellation procedures were optimized and compared employing a periodic signal source.

  9. Towards a complete Fermi surface in underdoped high Tc superconductors

    NASA Astrophysics Data System (ADS)

    Harrison, Neil

    The discovery of magnetic quantum oscillations in underdoped high Tc superconductors raised many questions, and initiated a quest to understand the origin of the Fermi surface the like of which had not been seen since the very first discovery of quantum oscillations in elemental bismuth. While studies of the Fermi surface of materials are today mostly assisted by computer codes for calculating the electronic band structure, this was not the case in the underdoped high Tc materials. The Fermi surface was shown to reconstructed into small pockets, yet there was no hint of a viable order parameter. Crucial clues to understanding the origin of the Fermi surface were provided by the small value of the observed Fermi surface cross-section, the negative Hall coefficient and the small electronic heat capacity at high magnetic fields. We also know that the magnetic fields were likely to be too weak to destroy the pseudogap and that vortex pinning effects could be seen to persist to high magnetic fields at low temperatures. I will show that the Fermi surface that appears to fit best with the experimental observations is a small electron pocket formed by connecting the nodal `Fermi arcs' seen in photoemission experiments, corresponding to a density-wave state with two different orthogonal ordering vectors. The existence of such order has subsequently been detected by x-ray scattering experiments, thereby strengthening the case for charge ordering being responsible for reconstructing the Fermi surface. I will discuss new efforts to understand the relationship between the charge ordering and the pseudogap state, discussing the fate of the quasiparticles in the antinodal region and the dimensionality of the Fermi surface. The author acknowledges contributions from Suchitra Sebastian, Brad Ramshaw, Mun Chan, Yu-Te Hsu, Mate Hartstein, Gil Lonzarich, Beng Tan, Arkady Shekhter, Fedor Balakirev, Ross McDonald, Jon Betts, Moaz Altarawneh, Zengwei Zhu, Chuck Mielke, James Day, Doug

  10. High Tc layered ferrielectric crystals by coherent spinodal decomposition

    DOE PAGES

    Susner, Michael A.; Belianinov, Alex; Borisevich, Albina Y.; ...

    2015-11-13

    Research in the rapidly-developing field of 2D-electronic materials has thus far been focused on metallic and semiconducting materials. However, complementary dielectric materials such as non-linear dielectrics are needed to enable realistic device architectures. Candidate materials require tunable dielectric properties and pathways for heterostructure assembly. Here we report on a family of cation-deficient transition metal thiophosphates whose unique chemistry makes them a viable prospect for these applications. In these materials, naturally occurring ferrielectric heterostructures composed of centrosymmetric In4/3P2S6 and ferrielectrically-active CuInP2S6 are realized by controllable chemical phase separation in van-der-Waals bonded single crystals. CuInP2S6 by itself is a layered ferrielectric withmore » Tc just over room-temperature which rapidly decreases with homogenous doping. Surprisingly, in our composite materials, the ferrielectric Tc of the polar CuInP2S6 phase increases. This effect is enabled by unique spinodal decomposition that retains the overall van-der-Waals layered morphology of the crystal, but chemically separates CuInP2S6 and In4/3P2S6 within each layer. The average spatial periodicity of the distinct chemical phases can be finely controlled by altering the composition and/or synthesis conditions. One intriguing prospect for such layered spinodal alloys is large volume synthesis of 2D in-plane heterostructures with periodically alternating polar and non-polar phases.« less

  11. Experimental study of 99mTc-aluminum oxide use for sentinel lymph nodes detection

    NASA Astrophysics Data System (ADS)

    Chernov, V. I.; Sinilkin, I. G.; Zelchan, R. V.; Medvedeva, A. A.; Lyapunov, A. Yu.; Bragina, O. D.; Varlamova, N. V.; Skuridin, V. S.

    2016-08-01

    The purpose of the study was a comparative research in the possibility of using the radiopharmaceuticals 99mTc-Al2O3 and 99mTc-Nanocis for visualizing sentinel lymph nodes. The measurement of the sizes of 99mTc-Al2O3 and 99mTc-Nanocis colloidal particles was performed in seven series of radiopharmaceuticals. The pharmacokinetics of 99mTc-Al2O3 and 99mTc-Nanocis was researched on 50 white male rats. The possibility of the use of 99mTc-Al2O3 and 99mTc-Nanocis for lymphoscintigraphy was studied in the experiments on 12 white male rats. The average dynamic diameter of the sol particle was 52-77 nm for 99mTc-Al2O3 and 16.7-24.5 nm for 99mTc-Nanocis. Radiopharmaceuticals accumulated in the inguinal lymph node in 1 hour after administration; the average uptake of 99mTc-Al2O3 was 8.6% in it, and the accumulation of 99mTc-Nanocis was significantly lower—1.8% (p < 0.05). In all study points the average uptake of 99mTc-Al2O3 in the lymph node was significantly higher than 99mTc-Nanocis accumulation. The results of dynamic scintigraphic studies in rats showed that 99mTc-Al2O3 and 99mTc-Nanocis actively accumulated into the lymphatic system. By using 99mTc-Al2O3 inguinal lymph node was determined in 5 minutes after injection and clearly visualized in all the animals in the 15th minute, when the accumulation became more than 1% of the administered dose. Further observation indicated that the 99mTc-Al2O3 accumulation reached a plateau in a lymph node (average 10.5%) during 2-hour study and then its accumulation remained practically at the same level, slightly increasing to 12% in 24 hours. In case of 99mTc-Nanocis inguinal lymph node was visualized in all animals for 15 min when it was accumulated on the average 1.03% of the administered dose. Plateau of 99mTc-Nanocis accumulation in the lymph node (average 2.05%) occurred after 2 hours of the study and remained almost on the same level (in average 2.3%) for 24 hours. Thus, the experimental study of a new domestic

  12. Design and performance of an automated radionuclide separator: its application on the determination of ⁹⁹Tc in groundwater.

    PubMed

    Chung, Kun Ho; Choi, Sang Do; Choi, Geun Sik; Kang, Mun Ja

    2013-11-01

    A modular automated radionuclide separator for (99)Tc (MARS Tc-99) has been developed for the rapid and reproducible separation of technetium in groundwater samples. The control software of MARS Tc-99 was developed in the LabView programming language. An automated radiochemical method for separating (99)Tc was developed and validated by the purification of (99m)Tc tracer solution eluted from a commercial (99)Mo/(99m)Tc generator. The chemical recovery and analytical time for this radiochemical method were found to be 96 ± 2% and 81 min, respectively.

  13. Usage of radiopharmaceuticals in the development of pharmaceutical drug delivery systems: validation of [99mTc]DTPA and [99mTc]ECD.

    PubMed

    Terán, Mariella; Savio, Eduardo; Paolino, Andrea; Frier, Malcolm

    2004-03-01

    Tablets containing drugs of different lipophilicity, ranitidine and cinarizine, and placebo were prepared and their in vitro behaviour was studied by dissolution and disintegration tests. [(99m)Tc]Diethylenetriamine-pentaacetic acid ([(99m)Tc]DTPA) and [(99m)Tc]ethyl cysteinate dimer ([(99m)Tc]ECD) were used as tracers of the process. Both of them were added to tablets during wet granulation. Dissolution and disintegration profiles were assessed at different pH values (1, 4 and 7). Radioactivity was evaluated in filtered samples and scintigraphic studies were carried out in gamma camera. Stability in dissolution media was confirmed for both tracers under these conditions. Dissolution and disintegration velocity constants were calculated. [(99m)Tc]DTPA proved to be an appropriate tracer for polar drugs such as ranitidine. Nevertheless, it was not a suitable tracer for lipophilic active drugs such as cinarizine. On the other hand, the most lipophilic tracer, [(99m)Tc]ECD, exhibited the opposite behaviour. Scintigraphic studies of the disintegration process did not show significant differences between placebos and tablets containing active drugs. As disintegration is a physical process it does not discriminate between chemical differences in tablet formulations. Both methods complement each other because the dissolution process can be followed when a suitable radiotracer is chosen according to the physicochemical characteristics of the active drug.

  14. Complete Genome Sequence of the Intracellular Bacterial Symbiont TC1 in the Anaerobic Ciliate Trimyema compressum.

    PubMed

    Shinzato, Naoya; Aoyama, Hiroaki; Saitoh, Seikoh; Nikoh, Naruo; Nakano, Kazuma; Shimoji, Makiko; Shinzato, Misuzu; Satou, Kazuhito; Teruya, Kuniko; Hirano, Takashi; Yamada, Takanori; Nobu, Masaru K; Tamaki, Hideyuki; Shirai, Yumi; Park, Sanghwa; Narihiro, Takashi; Liu, Wen-Tso; Kamagata, Yoichi

    2016-09-22

    A free-living ciliate, Trimyema compressum, found in anoxic freshwater environments harbors methanogenic archaea and a bacterial symbiont named TC1 in its cytoplasm. Here, we report the complete genome sequence of the TC1 symbiont, consisting of a 1.59-Mb chromosome and a 35.8-kb plasmid, which was determined using the PacBio RSII sequencer.

  15. Imaging of Cerebral Amyloid Angiopathy with Bivalent 99mTc-Hydroxamamide Complexes

    NASA Astrophysics Data System (ADS)

    Iikuni, Shimpei; Ono, Masahiro; Watanabe, Hiroyuki; Matsumura, Kenji; Yoshimura, Masashi; Kimura, Hiroyuki; Ishibashi-Ueda, Hatsue; Okamoto, Yoko; Ihara, Masafumi; Saji, Hideo

    2016-05-01

    Cerebral amyloid angiopathy (CAA), characterized by the deposition of amyloid aggregates in the walls of cerebral vasculature, is a major factor in intracerebral hemorrhage and vascular cognitive impairment and is also associated closely with Alzheimer’s disease (AD). We previously reported 99mTc-hydroxamamide (99mTc-Ham) complexes with a bivalent amyloid ligand showing high binding affinity for β-amyloid peptide (Aβ(1–42)) aggregates present frequently in the form in AD. In this article, we applied them to CAA-specific imaging probes, and evaluated their utility for CAA-specific imaging. In vitro inhibition assay using Aβ(1–40) aggregates deposited mainly in CAA and a brain uptake study were performed for 99mTc-Ham complexes, and all 99mTc-Ham complexes with an amyloid ligand showed binding affinity for Aβ(1–40) aggregates and very low brain uptake. In vitro autoradiography of human CAA brain sections and ex vivo autoradiography of Tg2576 mice were carried out for bivalent 99mTc-Ham complexes ([99mTc]SB2A and [99mTc]BT2B), and they displayed excellent labeling of Aβ depositions in human CAA brain sections and high affinity and selectivity to CAA in transgenic mice. These results may offer new possibilities for the development of clinically useful CAA-specific imaging probes based on the 99mTc-Ham complex.

  16. Simulation of the direct production of 99mTc at a small cyclotron

    NASA Astrophysics Data System (ADS)

    Eslami, M.; Kakavand, T.

    2014-06-01

    Usually 99mTc is produced indirectly through generator 99Mo/99mTc. In the present study, the direct production of this radioisotope by charged particle irradiation was investigated using Monte Carlo method. After scouting of the reactions that produce 99mTc, excitation functions of these reactions were predicted by optical model components in the TALYS-1.6 code. Suitable energy range of projectile for this production was selected by spotting of maximum cross section and minimum impurity due to other emission channels. Then target geometry was designed based on stopping power calculation by the SRIM code. Thick target yield of 100Mo(p,2n)99mTc, 98Mo(p,γ)99mTc and natMo(p,x)99mTc reactions was predicted by the result of excitation function and stopping power calculations. Finally, 100Mo(p,2n)99mTc reaction was selected as a primary reaction for the direct production of 99mTc and its process was simulated by employing the MCNPX code to calculate the energy distribution of proton in the 100Mo target body and estimation of residual nuclei during irradiation. Good agreement was obtained between the experimental, the theoretical, and the simulation-based (analytical and directly) production yields. This study demonstrated that Monte Carlo provides a method for the design and optimization of targets for the radionuclide production purposes.

  17. Assessment of RELAP5/MOD3 Version 7 based on the BETHSY Test 6. 2 TC

    SciTech Connect

    Choi, C.J. ); Roth, P.A.; Schultz, R.R. )

    1992-01-01

    This document provides a discussion of the BETHSY test 6.2 TC which was conducted to investigate thermal hydraulic phenomena during a 5% cold leg SBLOCA and to provide high quality data for advanced thermal-hydraulic code assessment. BETHSY test 6.2 TC was analyzed using RELAP5/MOD3 version 7o.

  18. [Evaluation of multiple myeloma with bone scintigraphy using Tc 99 diphosphonate. Review of the literature].

    PubMed

    Solis, O J; Gonzales, R; De Luca, S; McKusick, K A; Potsaid, M S

    1977-04-01

    Bone Scanning using 99m Tc-Diphosphonate is another diagnostic modality in the evaluation of multiple mieloma which allows the identification of bone lesions not demonstrable by conventional radiography. The use of 99m Tc-Diphosphonate is more convenient and less harmful than other radioactive isotopes utilized before.

  19. Imaging endocarditis with Tc-99m-labeled antibody--an experimental study: concise communication

    SciTech Connect

    Wong, D.W.; Dhawan, V.K.; Tanaka, T.; Mishkin, F.S.; Reese, I.C.; Thadepalli, H.

    1982-03-01

    The sensitivity and specificity of Tc-99m-labeled antibacterial antibody (Tc-99m Ab) for detecting bacterial endocarditis were evaluated in an experimental model. Rabbit-produced antistaphylococcal antibody was extracted using Rivanol and chemically labeled with Tc-99m. This Tc-99m Ab was injected intravenously in New Zealand rabbits 24 hr after producing Staphylococcus aureus endocarditis of the aortic valve. Imaging and tissue analyses were performed on the following day. All 11 animals developed S. aureus aortic-valve vegetations and showed increased uptake of Tc-99m Ab at the aortic valve, 118 times higher than at the uninfected tricuspid valve. Although high hepatic radioactivity and anatomic uncertainties interfered with in vivo delineation of these lesions, images of the excised hearts showed all affected valves. Two rabbits inoculated with Escherichia coli did not develop endocarditis and had little uptake of Tc-99m Ab, while six rabbits with enterococcal endocarditis had no uptake of the Tc-99m Ab in their vegetations. The findings suggest potential value of Tc-99m Ab on the rapid diagnosis of endocarditis.

  20. Anomalous optical conductivity in the normal state of high Tc oxides

    NASA Astrophysics Data System (ADS)

    Moriya, Toru; Takahashi, Yoshinori

    1991-03-01

    The optical resistivity due to antiferromagnetic spin fluctuations in two-dimensional metals, as a possible model for high Tc oxides, is calculated within the Born approximation and the self-consistent renormalization (SCR) theory for the spin fluctuations. The result is shown to explain the observed anomalous behavior of optical conductivity in YBa2Cu3O7 above Tc quantitatively.

  1. What Can We Learn From Two Consecutive Cases? Droperidol May Abolish TcMEPs

    PubMed Central

    González, Ángel Saponaro; Lorensu, Pedro Javier Pérez; Gómez, Santiago Chaves; Medina, Josué Francisco Nodarse; Dios, Jose Ángel Torres

    2017-01-01

    Droperidol is a D2 receptor antagonist currently used in Europe for preventing postoperative nausea and vomiting. It was used to perform neurolept anaesthesia in combination with fentanyl until a Food and Drug Administration (FDA) ‘black box’ warning restricted its use due to cardiovascular side effects in 2001. There is no literature regarding the effects of droperidol on transcranial motor evoked potentials (TcMEPs) elicited by electrical stimulation. Our aim was to report two cases of spine surgery in which TcMEPs were lost due to droperidol administration. We report the cases of a 4-year-old male with scoliosis undergoing correction and a 58-year-old woman with metastasis on the D8 vertebrae undergoing kyphosis correction. Intraoperative neurophysiological monitoring was achieved through TcMEPs and somatosensory evoked potentials (SEPs). Intraoperative neurophysiological monitoring (IONM) showed a temporal loss of TcMEPs without SEPs changes coinciding with the administration of droperidol. TcMEP stimulation parameters were changed to double train of pulses, with the aim to elicit them, obtaining responses. Five minutes after droperidol administration, TcMEPs were equal to those at baseline. Droperidol used as prophylaxis for postoperative nausea abolishes TcMEPs. Changing stimulation parameters to double train of pulses, it allows to bypass droperidol central action, achieving monitorable TcMEPs. PMID:28377841

  2. Incidental 99mTc-DTPA Uptake in Tarlov Cysts on Radionuclide SPECT/CT Cisternography.

    PubMed

    Vamadevan, Shankar; Le, Ken; Bui, Chuong; Mansberg, Robert

    2017-04-01

    Sacral perineural cysts are also known as Tarlov cysts. A 58-year-old man with suspected intracranial hypotension was evaluated with Tc-DTPA radionuclide cisternography. Radionuclide planar and SPECT/CT cisternography revealed Tc-DTPA uptake in sacral lesions. Spine MRI confirmed Tarlov cysts at the S1 and S2 levels.

  3. 99Tc(VII) Retardation, Reduction, and Redox Rate Scaling in Naturally Reduced Sediments

    SciTech Connect

    Liu, Yuanyuan; Liu, Chongxuan; Kukkadapu, Ravi K.; McKinley, James P.; Zachara, John M.; Plymale, Andrew E.; Miller, Micah D.; Varga, Tamas; Resch, Charles T.

    2015-10-15

    Abstract: An experimental and modeling study was conducted to investigate pertechnetate (Tc(VII)) retardation, reduction, and rate scaling in three sediments from Ringold formation at U.S. Department of Energy’s Hanford site, where 99Tc is a major contaminant in groundwater. Tc(VII) was reduced in all the sediments in both batch reactors and diffusion columns, with a faster rate in a sediment containing a higher concentration of HCl-extractable Fe(II). Tc(VII) migration in the diffusion columns was reductively retarded with retardation degrees correlated with Tc(VII) reduction rates. The reduction rates were faster in the diffusion columns than those in the batch reactors, apparently influenced by the spatial distribution of redox-reactive minerals along transport paths that supplied Tc(VII). X-ray computed tomography and autoradiography were performed to identify the spatial locations of Tc(VII) reduction and transport paths in the sediments, and results generally confirmed the newly found behavior of reaction rate changes from batch to column. The results from this study implied that Tc(VII) migration can be reductively retarded at Hanford site with a retardation degree dependent on reactive Fe(II) content and its distribution in sediments. This study also demonstrated that an effective reaction rate may be faster in transport systems than that in well-mixed reactors.

  4. /sup 99m/Tc pertechnetate uptake in a thymoma: case report

    SciTech Connect

    Wilson, R.L.; Cowan, R.J.

    1982-04-01

    A case is reported to /sup 99m/Tc pertechnetate accumulation within an anterior mediastinal thymoma during a search for substernal goiter. This reemphasizes the non-specificity of /sup 99m/Tc pertechnetate uptake and the need for caution in using this agent to detect ectopic thyroid tissue.

  5. Heterogeneous Reduction of Tc(VII) by Fe(II) at the Solid-Water Interface

    SciTech Connect

    Peretyazhko, Tetyana; Zachara, John M.; Heald, Steve M.; Jeon, Byong Hun; Kukkadapu, Ravi K.; Liu, Chongxuan; Moore, Dean A.; Resch, Charles T.

    2008-03-15

    Technetium-99 is a byproduct of uranium fission. It exists in two stable valence states (IV/VII) and exhibits a half-cell potential of intermediate value (Eo = 0.748 V). The oxidized form of 99Tc [pertechnetate, TcO4-] is an oxyanion that sorbs poorly to amphoteric surfaces and forms few solid phases with geochemically relevant cations. It is consequently highly mobile in oxic water-rock systems. The reduced valence state [Tc(IV)] is relatively insoluble (<10-8 mol L-1), and, hence immobile as an oxyhydroxide precipitate [TcO2•nH2O(s)]. In spite of favorable thermodynamics, Tc(VII) reacts slowly with Fe2+(aq) under anoxic conditions. Experiments were performed herein to investigate the rates and products of heterogeneous reduction of Tc(VII) by Fe(II) sorbed to hematite and goethite, and by structural Fe(II) in a dithionite-citrate-bicarbonate (DCB) reduced natural phyllosilicate mixture containing vermiculite, illite, and muscovite. The heterogeneous reduction of Tc(VII) by Fe(II) sorbed to the Fe(III) oxides increased with increasing pH and was coincident with a second event of Fe2+(aq) adsorption. The reaction was almost instantaneous above pH 7. In contrast, the reduction rates of Tc(VII) by structural Fe(II) in the DCB-reduced phyllollsilicates, were not sensitive to pH or the concentration of ion-exchangeable Fe(II), and were orders of magnitude slower than observed for the Fe(III) oxides. Tc-EXAFS spectroscopy revealed that the reduction products were virtually identical on hematite and goethite that were comprised primarily of sorbed octahedral TcO2 monomers and dimers with significant Fe(III) in the second coordination shell. The nature of heterogeneous Fe(III) resulting from the redox reaction was ambiguous as probed by Tc-EXAFS spectroscopy, although Mössbauer spectroscopy applied to an experiment with 56Fe-goethite with adsorbed 57Fe(II) implied that redox product Fe(III) was goethite-like. The Tc(IV) reduction product formed on the DCB

  6. New Trend in THz Detection: High Tc Superconducting Hot Electron Bolometer Technology May Exhibit Advantage vs Low Tc Devices

    NASA Astrophysics Data System (ADS)

    Kreisler, A. J.; Degardin, A. F.; Aurino, M.; Peroz, C.; Villegier, J.-C.; Beaudin, G.; Delorme, Y.; Redon, M.; Sentz, A.

    2007-07-01

    Superconducting hot electron bolometer (HEB) mixers are a competitive alternative to conventional mixer technologies in the terahertz range because of their ultrawide bandwidth, high conversion gain, and low intrinsic noise level, even at 77 K. A technological process to realize HEBs based on high-Tc YBa2Cu3O7-zeta (YBCO) materials is described. Ultrathin 12 to 40 nm layers were sputtered on MgO (100) substrates, sub-micrometer constrictions (0.5 micrometer x 0.5 micrometer) were etched on these and log-periodic gold antennas were then integrated. Good superconducting properties were measured after the whole process. Electrical transport characteristics of the device are discussed, ageing effects are considered and regular bolometric THz response results are given.

  7. Infected knee prosthesis: diagnosis with In-111 leukocyte, Tc-99m sulfur colloid, and Tc-99m MDP imaging

    SciTech Connect

    Palestro, C.J.; Swyer, A.J.; Kim, C.K.; Goldsmith, S.J. )

    1991-06-01

    Forty-one possible cases of infected total knee prostheses studied with indium-111-labeled leukocyte scintigraphy were retrospectively reviewed. Twenty-four of the prostheses were studied with technetium-99m methylene diphosphonate bone scintigraphy and 19 with Tc-99m sulfur colloid marrow scintigraphy. Nine prostheses were infected, and 32 were uninfected. The accuracy of combined labeled leukocyte and sulfur colloid marrow imaging (95%) was higher than that of labeled leukocyte scintigraphy alone (78%), bone scintigraphy alone (74%), or combined labeled leukocyte and bone scintigraphy (75%). The authors conclude that combined labeled leukocyte and sulfur colloid imaging is an accurate method for diagnosis of infected knee prostheses. In this series, this technique was superior to labeled leukocyte and bone imaging, alone or in combination.

  8. Passport, a native Tc1 transposon from flatfish, is functionally active in vertebrate cells.

    PubMed

    Clark, Karl J; Carlson, Daniel F; Leaver, Michael J; Foster, Linda K; Fahrenkrug, Scott C

    2009-03-01

    The Tc1/mariner family of DNA transposons is widespread across fungal, plant and animal kingdoms, and thought to contribute to the evolution of their host genomes. To date, an active Tc1 transposon has not been identified within the native genome of a vertebrate. We demonstrate that Passport, a native transposon isolated from a fish (Pleuronectes platessa), is active in a variety of vertebrate cells. In transposition assays, we found that the Passport transposon system improved stable cellular transgenesis by 40-fold, has an apparent preference for insertion into genes, and is subject to overproduction inhibition like other Tc1 elements. Passport represents the first vertebrate Tc1 element described as both natively intact and functionally active, and given its restricted phylogenetic distribution, may be contemporaneously active. The Passport transposon system thus complements the available genetic tools for the manipulation of vertebrate genomes, and may provide a unique system for studying the infiltration of vertebrate genomes by Tc1 elements.

  9. Analysis and characterization of high- Tc superconducting planar transmission lines for microwave circuit components

    SciTech Connect

    Kong Keonshik.

    1991-01-01

    A loss modeling of high {Tc} superconducting planar transmission lines is presented in this dissertation. Transmission structures such as microstrip lines, coplanar waveguides and conductor backed coplanar waveguides are investigated for implementation of a high-{Tc} superconductor. Also, short pulse propagation in the superconducting coplanar stripline is characterized. The motivation for this work is to provide an analytical basis for the effective application of a high {Tc} superconductor to planar transmission lines for microwave components. First, a loss characterization of the various high {Tc} superconducting microstrip line structures is presented in which either the strip or the ground plane is a high {Tc} superconductor. In the analysis, the internal impedances in the strip and the ground plane are separately calculated, and the total internal impedance is obtained by the superposition of the internal impedances. Next, the characteristic of a superconducting coplanar waveguide is investigated and compared with a superconducting microstrip line.

  10. The uptake of TcO-4 by plants: A mathematical description

    SciTech Connect

    Van Loon, L.R.; Desmet, G.M.; Cremers, A. )

    1989-08-01

    A model describing the uptake of TcO-4 by spinach plants was developed. The equation relates both plant and soil parameters (e.g., growth, metabolism, concentration of TcO-4 and composition of the growth medium) to the concentration of Tc in the shoot of the plant. As the soil solution is the medium from which plants obtain nutrients and non-nutrients, the modeling parameters have been obtained from uptake experiments using nutrient solutions (= simulated soil solutions) as the growth medium. Two important model assumptions are: (1) that an equilibrium exists between TcO-4 in the plant and the growth medium and (2) that the leaf TcO-4 metabolism is a pseudofirst order reaction occurring in a non-constant volume.

  11. Jasmonate-responsive expression of paclitaxel biosynthesis genes in Taxus cuspidata cultured cells is negatively regulated by the bHLH transcription factors TcJAMYC1, TcJAMYC2, and TcJAMYC4

    PubMed Central

    Lenka, Sangram K.; Nims, N. Ezekiel; Vongpaseuth, Kham; Boshar, Rosemary A.; Roberts, Susan C.; Walker, Elsbeth L.

    2015-01-01

    Taxus cell suspension culture is a sustainable technology for the industrial production of paclitaxel (Taxol®), a highly modified diterpene anti-cancer agent. The methyl jasmonate (MJ)-mediated paclitaxel biosynthetic pathway is not fully characterized, making metabolic engineering efforts difficult. Here, promoters of seven genes (TASY, T5αH, DBAT, DBBT, PAM, BAPT, and DBTNBT), encoding enzymes of the paclitaxel biosynthetic pathway were isolated and used to drive MJ-inducible expression of a GUS reporter construct in transiently transformed Taxus cells, showing that elicitation of paclitaxel production by MJ is regulated at least in part at the level of transcription. The paclitaxel biosynthetic pathway promoters contained a large number of E-box sites (CANNTG), similar to the binding sites for the key MJ-inducible transcription factor AtMYC2 from Arabidopsis thaliana. Three MJ-inducible MYC transcription factors similar to AtMYC2 (TcJAMYC1, TcJAMYC2, and TcJAMYC4) were identified in Taxus. Transcriptional regulation of paclitaxel biosynthetic pathway promoters by transient over expression of TcJAMYC transcription factors indicated a negative rather than positive regulatory role of TcJAMYCs on paclitaxel biosynthetic gene expression. PMID:25767476

  12. Synopsis of French experimental and in situ research on the terrestrial and marine behavior of Tc.

    PubMed

    Masson, M; Patti, F; Colle, C; Roucoux, P; Grauby, A; Saas, A

    1989-08-01

    Terrestrial environment studies have been essentially concerned with the evolution of soil deposition and soil-plant transfers. Experimentally determined coefficients of distribution in soils are low: 60-80% of Tc remains hydrosoluble during the first months. Technetium emissions resulting from microbiological activity have been quantified. Antagonistic effects on Mo and Tc retention by soils are dependent on their respective concentrations. Four areas of soil-plant transfers have been studied: 1) root absorption kinetics relative to deposition of Tc, 2) interaction of stable Mo (environmental parameter) with the transfer of Tc to plants, 3) interaction of some long-lived radioisotopes (effluent parameters) with the transfer of Tc to plants, and 4) long-term soil-plant transfer and aging of deposited material. Of aquatic systems, only the marine environment has been studied. Under anoxic conditions in the presence of reducing sediments, the distribution coefficients (Kd) were very high (10(3)). Concentration factors (CF) from water to organisms were generally very low (1 to 10); however, CF greater than 1000 have been observed for some biota such as macrophytic brown algae, worms and lobsters. Biochemical analysis showed that Tc was essentially free and partially bonded to proteins. The transfer factors between sediments and species were very low (TF less than 0.5). The biological half-time was determined in some marine organisms that had accumulated Tc from water, food or sediments; the loss is biphasic. Uptake in edible parts was low. The physiochemical form affects the accumulation and loss of Tc. Analyses have quantified 99Tc in marine fauna and biota in the English Channel in relation with releases of the reprocessing plant of La Hague. Brown algae are the best bioindicators for following 99Tc dispersion in marine ecosystems.

  13. Bioaccumulation and distribution of /sup 95m/Tc in an experimental freshwater pond

    SciTech Connect

    Blaylock, B.G.; Frank, M.L.

    1981-01-01

    An acute release of /sup 95m/Tc was made to a small experimental freshwater pond to determine the behavior of technetium in a freshwater ecosystem. The objectives of the study were (1) to determine the distribution of /sup 95m/Tc in the components of the ecosystem and (2) to determine the concentration in freshwater biota. Prior to the release of /sup 95m/Tc, the pond was stocked with aquatic macrophytes, fish, and invertebrates. All components of the pond were sampled for a period of 37 d. Analyses of filtered and unfiltered water samples showed that /sup 95m/Tc did not sorb significantly to particulates suspended in the water but remained dissolved. Sediments accumulated /sup 95m/Tc slowly as the experiment progressed. In the biota, periphyton accumulated /sup 95m/Tc rapidly, reaching the highest concentration (3482 dpm/g dry wt) 4 h after the release and maintaining a relatively high concentration throughout the experiment. Fish and invertebrates accumulated /sup 95m/Tc gradually. Elimination studies and tissue analyses showed that a large percentage of the body burden was in the digestive system of all fish, suggesting that fish were accumulating /sup 95m/Tc through the food chain. Biological half-lives determined from elimination studies for carp (Cyprinus carpio), mosquitofish (Gambusia affinis), and snails (Helisoma sp.) were 2.5, 4.3, and 21.3 d, respectively. Calculated concentration factors for the same species were 11 for carp, 75 for mosquito fish, and 121 for snails. The estimated size of the biomass components in the ecosystem in descending order were: periphyton, macrophytes, invertebrates, fish, and algae. Based on biomass estimates and concentrations of the /sup 95m/Tc in the aquatic biota, approximately 1% of the /sup 95m/Tc accumulated in the biota.

  14. Noninvasive imaging of radiolabeled exosome-mimetic nanovesicle using 99mTc-HMPAO

    PubMed Central

    Hwang, Do Won; Choi, Hongyoon; Jang, Su Chul; Yoo, Min Young; Park, Ji Yong; Choi, Na Eun; Oh, Hyun Jeong; Ha, Seunggyun; Lee, Yun-Sang; Jeong, Jae Min; Gho, Yong Song; Lee, Dong Soo

    2015-01-01

    Exosomes known as nano-sized extracellular vesicles attracted recent interests due to their potential usefulness in drug delivery. Amid remarkable advances in biomedical applications of exosomes, it is crucial to understand in vivo distribution and behavior of exosomes. Here, we developed a simple method for radiolabeling of macrophage-derived exosome-mimetic nanovesicles (ENVs) with 99mTc-HMPAO under physiologic conditions and monitored in vivo distribution of 99mTc-HMPAO-ENVs using SPECT/CT in living mice. ENVs were produced from the mouse RAW264.7 macrophage cell line and labeled with 99mTc-HMPAO for 1 hr incubation, followed by removal of free 99mTc-HMPAO. SPECT/CT images were serially acquired after intravenous injection to BALB/c mouse. When ENVs were labeled with 99mTc-HMPAO, the radiochemical purity of 99mTc-HMPAO-ENVs was higher than 90% and the expression of exosome specific protein (CD63) did not change in 99mTc-HMPAO-ENVs. 99mTc-HMPAO-ENVs showed high serum stability (90%) which was similar to that in phosphate buffered saline until 5 hr. SPECT/CT images of the mice injected with 99mTc-HMPAO-ENVs exhibited higher uptake in liver and no uptake in brain, whereas mice injected with 99mTc-HMPAO showed high brain uptake until 5 hr. Our noninvasive imaging of radiolabeled-ENVs promises better understanding of the in vivo behavior of exosomes for upcoming biomedical application. PMID:26497063

  15. 78 FR 30269 - Foreign-Trade Zone 129-Bellingham, Washington; Authorization of Production Activity; T.C. Trading...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-22

    ... Activity; T.C. Trading Company, Inc. (Eyeglass Assembly and Kitting), Blaine, WA On January 17, 2013, the... Foreign-Trade Zones (FTZ) Board on behalf of T.C. Trading Company, Inc., within Subzone 129B, in...

  16. Theory of high-TC superconductivity: transition temperature

    NASA Astrophysics Data System (ADS)

    Harshman, Dale R.; Fiory, Anthony T.; Dow, John D.

    2010-12-01

    After reading over our published manuscript, we noticed that the discussion concerning the determination of σ for the ruthenate Ba2YRu0.9Cu0.1O6 in section 2.3.1 (3rd paragraph) is somewhat terse. Herein we provide an expanded analysis which better explains our estimate of γ (and thus σ) for this compound. All numbers, figures and conclusions remain unaltered. The ruthenate compounds A2YRu1-xCuxO6 (with A = Ba or Sr; x = 0.05-0.15) are double-perovskites containing no cuprate planes and with ν = μ = 1 [1] (reference [82] in the paper). The determination of γ follows from equation (2.5b), wherein rule 1b introduces the factor 1/2. In the lower limit, one expects a minimum of ~2 charges per Cu dopant, which are shared between two charge reservoirs of each layer type (AO and 1/2 (YRu1-xCuxO4)), producing a net factor of unity. Thus, for Ba2YRu0.9Cu0.1O6 (with TC0 ~ 30-40 K), we estimate γ = (1/2)(1) = 1/2, yielding σ = 0.05 as stated by equation (2.5c) in the paper. While one may expect an average effective charge state for Ru near +5, and that of Cu to be between +2 and +3 (post anneal) [2], the lower-limit estimation provided, which places the corresponding data point in figure 2 to the left of the line, appears sufficient to include the ruthenates with the other high-TC compounds found to follow equation (2.6) so far. Owing to the uncertainty in the experimental values for TC0, as well as the Ru and Cu valence states, however, this compound was excluded in the data analyses presented. Future research will attempt a more accurate determination of the charge per doped Cu, and thus σ. We would also like to point out a typographical correction in the definition of the corresponding ruthenate type II reservoir in the last column of table 1, which should read 1/2 (YRu0.9Cu0.1O4). An unrelated item is found in the fourth line of section 2.3.3, where Tb(O0.80F0.20)FeAs should read Tb(O0.80-yF0.20)FeAs. Additionally, reference [132] is now known and has the form

  17. Role of CD8 Regulatory T Cells versus Tc1 and Tc17 Cells in the Development of Human Graft-versus-Host Disease

    PubMed Central

    Gutiérrez-Hoya, Adriana; López-Santiago, Rubén; Vela-Ojeda, Jorge; Montiel-Cervantes, Laura; Rodríguez-Cortés, Octavio; Rosales-García, Víctor; Flores-Mejía, Raúl; Sandoval-Borrego, Daniela

    2017-01-01

    CD8+ T cells that secrete proinflammatory cytokines play a central role in exacerbation of inflammation; however, a new subpopulation of CD8 regulatory T cells has recently been characterized. This study analyzes the prominent role of these different subpopulations in the development of graft-versus-host disease (GVHD). Samples from 8 healthy donors mobilized with Filgrastim® (G-CSF) and 18 patients who underwent allogeneic hematopoietic stem cell transplantation (HSCT) were evaluated by flow cytometry. Mobilization induced an increase in Tc1 (p < 0.01), Th1 (p < 0.001), Tc17 (p < 0.05), and CD8+IL-10+ cells (p < 0.05), showing that G-CSF induces both pro- and anti-inflammatory profiles. Donor-patient correlation revealed a trend (p = 0.06) toward the development of GVHD in patients who receive a high percentage of Tc1 cells. Patients with acute GVHD (aGVHD), either active or controlled, and patients without GVHD were evaluated; patients with active aGVHD had a higher percentage of Tc1 (p < 0.01) and Tc17 (p < 0.05) cells, as opposed to patients without GVHD in whom a higher percentage of CD8 Treg cells (p < 0.01) was found. These findings indicate that the increase in Tc1 and Tc17 cells is associated with GVHD development, while regulatory CD8 T cells might have a protective role in this disease. These tests can be used to monitor and control GVHD. PMID:28164135

  18. Role of CD8 Regulatory T Cells versus Tc1 and Tc17 Cells in the Development of Human Graft-versus-Host Disease.

    PubMed

    Gutiérrez-Hoya, Adriana; López-Santiago, Rubén; Vela-Ojeda, Jorge; Montiel-Cervantes, Laura; Rodríguez-Cortés, Octavio; Rosales-García, Víctor; Paredes-Cervantes, Vladimir; Flores-Mejía, Raúl; Sandoval-Borrego, Daniela; Moreno-Lafont, Martha

    2017-01-01

    CD8(+) T cells that secrete proinflammatory cytokines play a central role in exacerbation of inflammation; however, a new subpopulation of CD8 regulatory T cells has recently been characterized. This study analyzes the prominent role of these different subpopulations in the development of graft-versus-host disease (GVHD). Samples from 8 healthy donors mobilized with Filgrastim® (G-CSF) and 18 patients who underwent allogeneic hematopoietic stem cell transplantation (HSCT) were evaluated by flow cytometry. Mobilization induced an increase in Tc1 (p < 0.01), Th1 (p < 0.001), Tc17 (p < 0.05), and CD8(+)IL-10(+) cells (p < 0.05), showing that G-CSF induces both pro- and anti-inflammatory profiles. Donor-patient correlation revealed a trend (p = 0.06) toward the development of GVHD in patients who receive a high percentage of Tc1 cells. Patients with acute GVHD (aGVHD), either active or controlled, and patients without GVHD were evaluated; patients with active aGVHD had a higher percentage of Tc1 (p < 0.01) and Tc17 (p < 0.05) cells, as opposed to patients without GVHD in whom a higher percentage of CD8 Treg cells (p < 0.01) was found. These findings indicate that the increase in Tc1 and Tc17 cells is associated with GVHD development, while regulatory CD8 T cells might have a protective role in this disease. These tests can be used to monitor and control GVHD.

  19. Oxidative dissolution potential of biogenic and abiogenic TcO 2 in subsurface sediments

    NASA Astrophysics Data System (ADS)

    Fredrickson, James K.; Zachara, John M.; Plymale, Andrew E.; Heald, Steve M.; McKinley, James P.; Kennedy, David W.; Liu, Chongxuan; Nachimuthu, Ponnusamy

    2009-04-01

    Technetium-99 (Tc) is an important fission product contaminant associated with sites of nuclear fuels reprocessing and geologic nuclear waste disposal. Tc is highly mobile in its most oxidized state [Tc(VII)O4-] and less mobile in the reduced form [Tc(IV)O 2· nH 2O]. Here we investigate the potential for oxidation of Tc(IV) that was heterogeneously reduced by reaction with biogenic Fe(II) in two sediments differing in mineralogy and aggregation state; unconsolidated Pliocene-age fluvial sediment from the upper Ringold (RG) Formation at the Hanford Site and a clay-rich saprolite from the Field Research Center (FRC) background site on the Oak Ridge Site. Both sediments contained Fe(III) and Mn(III/IV) as redox active phases, but FRC also contained mass-dominant Fe-phyllosilicates of different types. Shewanella putrefaciens CN32 reduced Mn(III/IV) oxides and generated Fe(II) that was reactive with Tc(VII) in heat-killed, bioreduced sediment. After bioreduction and heat-killing, biogenic Fe(II) in the FRC exceeded that in RG by a factor of two. More rapid reduction rates were observed in the RG that had lower biogenic Fe(II), and less particle aggregation. EXAFS measurements indicated that the primary reduction product was a TcO 2-like phase in both sediments. The biogenic redox product Tc(IV) oxidized rapidly and completely in RG when contacted with air. Oxidation, in contrast, was slow and incomplete in the FRC, in spite of similar molecular scale speciation of Tc compared to RG. X-ray microprobe, electron microprobe, X-ray absorption spectroscopy, and micro X-ray diffraction were applied to the whole sediment and isolated Tc-containing particles. These analyses revealed that non-oxidizable Tc(IV) in the FRC existed as complexes with octahedral Fe(III) within intra-grain domains of 50-100 μm-sized, Fe-containing micas presumptively identified as celadonite. The markedly slower oxidation rates in FRC as compared to RG were attributed to mass

  20. Cationic lipophilic complexes of /sup 99/ /SUP m/ Tc and their use for myocardial and hepatobiliary imaging

    SciTech Connect

    Deutsch, E. A.; Glavan, K. A.

    1984-12-18

    A method of imaging organs with /sup 99/ /SUP m/ Tc radiopharmaceuticals, especially of hepatobiliary imaging and negative myocardial infarct imaging in a mammal which comprises administering to the mammal a hepatobiliary or myocardial imaging amount of a cationic lipophilic complex of Tc-99m and detecting the Tc-99m complex in the mammal. A method for the preparation of cationic lipophilic complexes of Tc-99m.

  1. Chemistry and biology of Tc-99m renal function radiopharmaceuticals. Final report, May 1, 1982-January 15, 1983

    SciTech Connect

    Not Available

    1983-01-01

    Progress is reported on research conducted during the period May 1, 1982 to January 15, 1983. The chemistry and biology of two possible renal function radiopharmaceuticals, Tc-99m N, N'-bis (mercaptoacetyl)-2,3-diamino-propanoate (Tc-99m CO/sub 2/DADS, 1(X=OH)) and the Tc-99m complex of penicillamine. (ACR)

  2. INFLUENCE OF NATURAL AND SYNTHETIC ORGANIC LIGANDS ON THE STABILITY AND MOBILITY OF REDUCED TC(IV)

    SciTech Connect

    Nathalie A. Wall; Baohua Gu

    2012-12-20

    The primary objectives were (1) to quantify the interactions of organic ligands with Tc(IV) through the generation of thermodynamic (complexation) and kinetic parameters needed to assess and predict the mobility of reduced Tc(IV) at DOE contaminated sites; and (2) to determine the impact of organic ligands on the mobility and fate of reduced Tc(IV) under field geochemical conditions.

  3. Focal 99mTc-DMSA Uptake in Lung Parenchyma Without Structural Alterations on SPECT/CT.

    PubMed

    Nursal, Gül Nihal; Reyhan, Mehmet; Yapar, Ali Fuat

    2015-11-01

    Static renal scintigraphy with Tc-DMSA is commonly used for the evaluation of renal morphology and function. Extrarenal uptake of Tc-DMSA is a rare finding described previously on sites such as bone metastasis, hemangioma, and splenic amyloidosis. We report a case with Tc-DMSA activity in the lungs.

  4. 78 FR 7395 - Foreign-Trade Zone 129-Bellingham, WA; Notification of Proposed Production Activity; T.C. Trading...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-01

    ... Activity; T.C. Trading Company, Inc. (Eyeglass Assembly and Kitting); Blaine, WA The Port of Bellingham, grantee of FTZ 129, submitted a notification of proposed production activity on behalf of T.C. Trading Company, Inc. (T.C. Trading), located in Blaine, Washington. The notification conforming to...

  5. Clinical comparison of I-131 orthoiodohippurate and the kit formulation of Tc-99m mercaptoacetyltriglycine

    SciTech Connect

    Taylor, A. Jr.; Ziffer, J.A.; Steves, A.; Eshima, D.; Delaney, V.B.; Welchel, J.D.

    1989-03-01

    Previous studies in animals and humans have shown that technetium-99m mercaptoacetyltriglycine (MAG3) purified by high-performance liquid chromatography is a renal tubular agent with characteristics similar to those of iodine-131 orthoiodohippurate (OIH). A kit formulation for Tc-99m MAG3 has been developed and compared with I-131 OIH in 17 patients with suspected renal dysfunction and three potential kidney donors. There were no adverse reactions. Tc-99m MAG3 images were of good quality and consistently better than I-131 OIH images. There was no significant difference in the relative renal uptake of Tc-99m MAG3 and I-131 OIH. The 30-minute urinary excretion of Tc-99m MAG3 was 36.4%, versus 40.4% for I-131 OIH. The average plasma clearance of Tc-99m MAG3 (138 mL/min +/- 117) was less than that of I-131 OIH (272 mL/min +/- 205) (P less than .001); however, there was good correlation between the Tc-99m MAG3 and I-131 OIH clearances (r = .87). The volume of distribution of Tc-99m MAG3 (5.96 L +/- 1.94) was less than that of I-131 OIH (9.41 L +/- 3.73) (P less than .001). These characteristics and the advantages of a simple kit formulation should lead to widespread clinical use.

  6. Quantitative simultaneous In-111/Tc-99m planar imaging in a long-bone infection phantom

    NASA Astrophysics Data System (ADS)

    Zhu, Xuping; Park, Mi-Ae; Gerbaudo, Victor H.; Moore, Stephen C.

    2007-12-01

    In-111-white-blood-cell and Tc-99m-sulfur-colloid dual-radionuclide imaging are frequently utilized in the evaluation of patients with suspected osteomyelitis. We have developed a quantitative planar imaging method in which Tc-99m and In-111 scans are acquired simultaneously in accurate spatial registration. Long, thin tubes containing only In-111 or Tc-99m were first imaged in a list mode within a water bath inclined with respect to the water surface; from these, 12 energy spectra corresponding to different Tc/In ratios were synthesized. Triple-energy-window (TEW) parameters for scatter and radionuclide crosstalk correction, including scatter windows and weights, were optimized using 100 noise realizations of each of the spectra (1200 total). A long-bone phantom containing a simulated infection site was then imaged in water with five In/Tc ratios; 100 noise realizations of two conjugate-view images were generated from each acquisition (500 total). Two regions of interest (ROIs) were defined, and the ratio of In/Tc count ratios in these two ROIs was evaluated with and without the TEW scatter correction and geometric mean attenuation compensation. The average bias improved from 17.2% to 5.3%, with comparable precision. TEW corrections with non-optimized but practical energy windows also improved the bias to 6.4%. Compared with subjective visual assessment, quantitation of In-111/Tc-99m ratios may improve diagnostic accuracy and could eventually permit grading of osteomyelitis.

  7. 99mTc-d-penicillamine-glucuronide: synthesis, radiolabeling, in vitro and in vivo evaluation.

    PubMed

    Teksöz, Serap; Içhedef, Ciğdem Acar; Ozyüncü, Seniha; Müftüler, Fazilet Zümrüt Biber; Unak, Perihan; Medine, Ilker Emin; Ertay, Türkan; Eren, Mine Şencan

    2011-10-01

    The current study was aimed at synthesizing a glucuronide derivative of D-penicillamine (D-PA) to be used for imaging purposes. First of all, D-PA-glucuronide (D-PA-Glu) was synthesized by experimental treatments starting with uridine 5'-diphospho-glucuronosyltransferase enzyme rich microsome preparate. Then, the synthesized compound was labeled with technetium ((99m)Tc) by using a reduction method with stannous chloride. Quality controls were performed by using high-performance liquid chromatography and thin-layer radio chromatography (TLRC). Radiolabeling yield of (99m)Tc-D-PA-Glu was more than 98% according to TLRC results. In vitro evaluations of radiolabeled complexes were investigated on PC-3 human prostate cancer cells. (99m)Tc-D-PA-Glu exhibited more accumulation on PC-3 cells versus (99m)Tc-D-PA at 240 minutes. In order to determine its radiopharmaceutical potential, biodistribution studies were carried out in male Albino Wistar rats. The biodistribution results of (99m)Tc-D-PA-Glu, showed the highest uptake in prostate at 120 minutes postinjection with the main excretion route being through kidneys and bladder. (99m)Tc-D-PA-Glu and (99m)Tc-D-PA have exhibited different biodistribution results.

  8. Impact of Mobile-Immoble Water on the Transport of Technetium (Tc-99) in Unsaturated Sediments

    NASA Astrophysics Data System (ADS)

    Jansik, D. P.; Wellman, D. M.; Cordova, E.; Wildenschild, D.

    2010-12-01

    Technetium has been released to the environment through nuclear power production and nuclear fuel processing; as a result, further spreading of Tc-99 is a concern at DOE sites across the US. The current body of work conducted on Tc-99 has provided a wealth of information regarding the redox relationships, sorption, solubility, and stability of the mineral phases, however little work has been conducted on the physical transport of the highly soluble pertechnetate oxyanion, in the subsurface. Current conceptual models do not explain the presence and persistence of the anion in deep vadose zone environments such as the Hanford, WA site. As new in situ remediation technologies are developed and remediation continues; it is necessary to understand implications for Tc-99 transport and mobilization in unsaturated systems. Specifically, foam and gas phase remediation could potentially alter established flow regimes by changing moisture content, flow paths, and surface reactivity of sediments; therefore, it is imperative to understand fundamental transport properties of Tc-99 in the context of physical and chemical constraints. Using an Unsaturated Flow Apparatus (UFA) we have conducted a series of experiments to examine the impact of mobile-immobile domains on the transport of Tc-99. By varying sand/silt ratios and saturations we examined how changes in pore morphology and moisture content impact the transport of Tc-99 within our experimental system. Results demonstrating the impact of sediment texture, pore morphology and soil moisture content on Tc-99 transport will be presented.

  9. The photoinduced transformation of fluorescent DNA base analogue tC triggers DNA melting.

    PubMed

    Preus, Søren; Jønck, Søren; Pittelkow, Michael; Dierckx, Anke; Karpkird, Thitinun; Albinsson, Bo; Wilhelmsson, L Marcus

    2013-08-01

    While fluorescent analogues of the canonical nucleobases have proven to be highly valuable in a large number of applications, up until today, fluorescent DNA base analogues remain virtually inapplicable for single-molecule fluorescence experiments which require extremely bright and photostable dyes. Insight into the photodegradation processes of these fluorophores is thus a key step in the continuous development towards dyes with improved performances. Here, we show that the commercially available fluorescent nucleobase analogue tC under intense long-term illumination and in the presence of O2 is degraded to form a single photoreaction product which we suggest to be the sulfoxide form of tC. The photoproduct is characterized by a blue-shifted absorption and a less intense fluorescence compared to that of tC. Interestingly, when tC is positioned inside double-stranded DNA this photodriven conversion of tC to its photoproduct greatly reduces the duplex stability of the overall double helix in which the probe is positioned. Since tC can be excited selectively at 400 nm, well outside the absorption band of the natural DNA bases, this observation points towards the application of tC as a general light-triggered switch of DNA duplex stability.

  10. The function of Sn(II)-apatite as a Tc immobilizing agent

    SciTech Connect

    Asmussen, R. Matthew; Neeway, James J.; Lawter, Amanda R.; Levitskaia, Tatiana G.; Lukens, Wayne W.; Qafoku, Nikolla P.

    2016-11-01

    Technetium-99 is a radioactive contaminant of high concern at many nuclear waste storage sites. At the U.S. Department of Energy Hanford Site, 99Tc is a component of low-activity waste (LAW) fractions of the nuclear tank waste, which are highly caustic, high ionic strength and have high concentrations of chromate. Removal of 99Tc from LAW streams would greatly benefit the site remediation process. In this study, we investigated the removal of 99Tc(VII), as pertechnetate, from deionized water (DIW) and a LAW simulant using two solid sorbents, tin (II) apatite (Sn-A) and SnCl2 through batch sorption testing and solid phase characterization. Sn-A showed higher levels of removal of Tc from both DIW and LAW simulant compared with the SnCl2. Scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/XEDS) and X-ray adsorption spectroscopy (XAS) of Sn-A following batch experiments in DIW showed that TcO4- is reduced to Tc(IV) on the Sn-A surface with no incorporation into the lattice structure of Sn-A. The performance of Sn-A in the LAW simulant was lowered due to a combined effect of the high alkalinity, which lead to an increased dissolution of Sn from the Sn-A, and a preference for the reduction of Cr(VI) over Tc(VII).

  11. Demonstrating alcoholic cirrhosis of the liver by Tc-99m BIDA scintigram

    SciTech Connect

    Shih, W.J.; DeLand, F.H.; Domstad, P.A.

    1984-08-01

    Six patients with decompensated cirrhosis of the liver underwent Tc-99m BIDA studies. All demonstrated 1) persistently high blood pool activity in the heart, lung, and soft tissue, 2) slow hepatic tracer uptake, 3) prolonged liver-to-bowel transit time, and 4) visualization of an enlarged spleen. Four of the six patients demonstrated evidence of ascites and in one patient there were visible collateral veins of the abdomen. These findings are due primarily to hepatic dysfunction and retaining Tc-99m BIDA in blood pool because of Tc-99m BIDA exclusively hepatic excretion and little or no alternative renal excretion. All six Tc-99m sulfur colloid studies were performed concomitantly. Except for bone marrow uptake and reversal of the normal liver-spleen ratio of radioactivity, the imaging abnormalities observed with Tc-99m BIDA were similar to those seen by Tc-99m SC. It is concluded that with Tc-99m BIDA studies, three of six abnormal findings, as described, suggest a decompensated stage of cirrhosis of the liver.

  12. Optical imaging of Tc-99m-based tracers: in vitro and in vivo results

    NASA Astrophysics Data System (ADS)

    Spinelli, Antonello E.; Meo, Sergio Lo; Calandrino, Riccardo; Sbarbati, Andrea; Boschi, Federico

    2011-11-01

    It has been recently shown that optical imaging (OI) methods can be used to image the in vivo biodistribution of several radiopharmaceuticals labeled with beta or alpha emitters. In this work particular attention has been focused on investigating the weaker optical signal induced by an almost pure gamma emitter like Tc-99m. Visible light emission measurements of a water solution containing Tc-99m were performed using a small animal OI system. A sequence of images was acquired for 24 h in order to study the decay of the luminescence signal. The difference between the luminescence decay half life and well-known Tc-99m half life was equal to 1%. in vivo imaging was performed by injecting one control nude mice with Tc-99m-MDP. Optical images obtained with equipment designed for bioluminescence imaging showed that a visible light emission was distinguishable and correctly localized in the bladder region where a higher concentration of Tc-99m-MDP was expected. The bladder to background ratio was always greater than 1. We conclude that the experimental data presented in this paper show that it is possible to detect in vivo luminescence optical photons induced by Tc-99m. This is important especially considering the large number of Tc-99m-based radiopharmaceutical currently available.

  13. Asteroid 2008 TC3 Breakup and Meteorite Fractions

    NASA Technical Reports Server (NTRS)

    Goodrich, C.; Jenniskens, P.; Shaddad, M. H.; Zolensky, M. E.; Fioretti, A. M.

    2017-01-01

    The recovery of meteorites from the impact of asteroid 2008 TC3 in the Nubian Desert of Sudan on October 7, 2008, marked the first time meteorites were collected from an asteroid observed in space by astronomical techniques before impacting. Search teams from the University of Khartoum traced the location of the strewn field and collected about 660 meteorites in four expeditions to the fall region, all of which have known fall coordinates. Upon further study, the Almahata Sitta meteorites proved to be a mixed bag of mostly ureilites (course grained, fine grained, and sulfide-metal assemblages), enstatite chondrites (EL3-6, EH3, EH5, breccias) and ordinary chondrites (H5-6, L4-5). One bencubbinite-like carbonaceous chondrite was identified, as well as one unique Rumuruti-like chondrite and an Enstatite achondrite. New analysis: The analysed meteorites so far suggest a high 30-40 percent fraction of non-ureilites among the recovered samples, but that high fraction does not appear to be in agreement with the meteorites in the University of Khartoum (UoK) collection. Ureilites dominate the meteorites that were recovered by the Sudanese teams. To better understand the fraction of recovered materials that fell to Earth, a program has been initiated to type the meteorites in the UoK collection in defined search areas. At this meeting, we will present some preliminary results from that investigation.

  14. Power Systems Development Facility Gasification Test Campaign TC17

    SciTech Connect

    Southern Company Services

    2004-11-30

    In support of technology development to utilize coal for efficient, affordable, and environmentally clean power generation, the Power Systems Development Facility (PSDF) located in Wilsonville, Alabama, routinely demonstrates gasification technologies using various types of coals. The PSDF is an engineering scale demonstration of key features of advanced coal-fired power systems, including a KBR (formerly Kellogg Brown & Root) Transport Gasifier, a hot gas particulate control device, advanced syngas cleanup systems, and high-pressure solids handling systems. This report summarizes the results gasification operation with Illinois Basin bituminous coal in PSDF test campaign TC17. The test campaign was completed from October 25, 2004, to November 18, 2004. System startup and initial operation was accomplished with Powder River Basin (PRB) subbituminous coal, and then the system was transitioned to Illinois Basin coal operation. The major objective for this test was to evaluate the PSDF gasification process operational stability and performance using the Illinois Basin coal. The Transport Gasifier train was operated for 92 hours using PRB coal and for 221 hours using Illinois Basin coal.

  15. High-Tc SQUID gradiometer system for immunoassays

    NASA Astrophysics Data System (ADS)

    Öisjöen, F.; Magnelind, P.; Kalabukhov, A.; Winkler, D.

    2008-03-01

    A high-Tc dc SQUID (superconducting quantum interference device) gradiometer was developed for magnetic immunoassays where magnetic nanoparticles are used as markers to detect biological reactions. The gradiometer was fabricated on a 5 × 10 mm2 SrTiO3 bicrystal substrate and has a gradiometer resolution of 2.1 pT cm-1 Hz-1/2. A magnetic signal was detected from a sample of 1 µl of Fe3O4 nanoparticles in a 40 mg ml-1 solution kept in a microcavity fabricated on Si wafers with Si3N4 membranes using MEMS (micro-electro-mechanical-systems) technology. It was found that volumes as small as 0.3 nl in principle would be detectable with our present device. This corresponds to a total number of particles of 2.2 × 107. The estimated average dipole moment per particle is 4.8 × 10-22 A m2. We are aiming at reading out immunoassays by detecting the Brownian relaxation of magnetic nanoparticles, and we also intend to integrate MEMS technology into our system.

  16. Power Systems Development Facility Gasification Test Campaign TC20

    SciTech Connect

    Southern Company Services

    2006-09-30

    In support of technology development to utilize coal for efficient, affordable, and environmentally clean power generation, the Power Systems Development Facility (PSDF), located in Wilsonville, Alabama, routinely demonstrates gasification technologies using various types of coal. The PSDF is an engineering scale demonstration of key features of advanced coal-fired power systems, including a Transport Gasifier, a hot gas particulate control device (PCD), advanced syngas cleanup systems, and high-pressure solids handling systems. This report summarizes the results of the first demonstration of the Transport Gasifier following significant modifications of the gasifier configuration. This demonstration took place during test campaign TC20, occurring from August 8 to September 23, 2006. The modifications proved successful in increasing gasifier residence time and particulate collection efficiency, two parameters critical in broadening of the fuel operating envelope and advancing gasification technology. The gasification process operated for over 870 hours, providing the opportunity for additional testing of various gasification technologies, such as PCD failsafe evaluation and sensor development.

  17. Power Systems Development Facility Gasification Test Campaign TC21

    SciTech Connect

    Southern Company Services

    2007-01-30

    In support of technology development to utilize coal for efficient, affordable, and environmentally clean power generation, the Power Systems Development Facility (PSDF), located in Wilsonville, Alabama, routinely demonstrates gasification technologies using various types of coal. The PSDF is an engineering scale demonstration of key features of advanced coal-fired power systems, including a Transport Gasifier, a hot gas particulate control device (PCD), advanced syngas cleanup systems, and high-pressure solids handling systems. This report summarizes the results of the first demonstration of gasification operation with lignite coal following the 2006 gasifier configuration modifications. This demonstration took place during test campaign TC21, occurring from November 7, 2006, through January 26, 2007. The test campaign began with low sodium lignite fuel, and after 304 hours of operation, the fuel was changed to high sodium lignite, for 34 additional hours of operation. Both fuels were from the North Dakota Freedom mine. Stable operation with low sodium lignite was maintained for extended periods, although operation with high sodium lignite was problematic due to agglomeration formation in the gasifier restricting solids circulation.

  18. The shape and rotation of asteroid 2008 TC3

    NASA Astrophysics Data System (ADS)

    Scheirich, Peter; Durech, Josef; Pravec, Petr; Kozubal, Marek; Dantowitz, Ron; Kaasalainen, Mikko; Betzler, Alberto Silva; Beltrame, Paolo; Muler, Gustavo; Birtwhistle, Peter; Kugel, Francois

    2010-10-01

    On October 6, 2008, a small F-class asteroid 2008 TC3 was discovered by Catalina Sky Survey telescope, and exploded 20 hr later in the Earth's atmosphere at 37 km altitude. We analyzed available photometric data taken from 6 October 21:10 to 7 October 01:46 UT, and created a numerical model of a shape and rotation state of the asteroid. The asteroid was in excited rotational state. We found two approximately mirror solutions of orientation of its angular momentum vector. Rotational and precession periods are 99.20 and 97.00 s (errors of the rotational period for the two solutions are 0.03 and 0.04 s; of the precession period are 0.05 s for both solutions). The volume of the convex model and the length of the longest axis of the dynamically equivalent, equal volume ellipsoid are ? and ?, where pV is surface geometric albedo. Assuming a mean albedo value for F taxonomic class, 0.049 ± 0.010, the volume is (25 ± 10) m3 and the longest axis is (6.7 ± 0.8) m. This volume of the convex model is an upper limit on a real volume of the asteroid, which may be less by up to 20% due to concavities.

  19. Terahertz imaging system using high-Tc superconducting oscillation devices

    NASA Astrophysics Data System (ADS)

    Tsujimoto, M.; Minami, H.; Delfanazari, K.; Sawamura, M.; Nakayama, R.; Kitamura, T.; Yamamoto, T.; Kashiwagi, T.; Hattori, T.; Kadowaki, K.

    2012-06-01

    Microwatt power oscillation devices at sub-terahertz frequency region between 0.3 and 1.0 terahertz (THz) were fabricated from high-Tc superconducting single crystalline Bi2Sr2CaCu2O8+δ and used as a source of the transmission terahertz imaging system. As test examples, terahertz images of coins and a razor blade placed inside the brownish paper envelopes with the spatial resolution of 1 mm are presented. The signal-to-noise ratio exceeds 130 in these images. Using a simple wedge-shaped interferometer and analysing the interference fringe pattern, the wavelength of the terahertz wave is calibrated within 0.1% accuracy. This interferometer also provides a simple method to measure the absorption coefficient of the liquid sample. Two test measurements for distilled water and ethanol are demonstrated and their absorption coefficients are obtained with 99.2% accuracy. This suggests that our terahertz imaging system can be applied to many practical applications, such as biological and biomedical imaging, environmental monitoring, microanalysis of impurities, structure and dynamical analyses of large molecules and ions in solution.

  20. The impact and recovery of asteroid 2008 TC(3).

    PubMed

    Jenniskens, P; Shaddad, M H; Numan, D; Elsir, S; Kudoda, A M; Zolensky, M E; Le, L; Robinson, G A; Friedrich, J M; Rumble, D; Steele, A; Chesley, S R; Fitzsimmons, A; Duddy, S; Hsieh, H H; Ramsay, G; Brown, P G; Edwards, W N; Tagliaferri, E; Boslough, M B; Spalding, R E; Dantowitz, R; Kozubal, M; Pravec, P; Borovicka, J; Charvat, Z; Vaubaillon, J; Kuiper, J; Albers, J; Bishop, J L; Mancinelli, R L; Sandford, S A; Milam, S N; Nuevo, M; Worden, S P

    2009-03-26

    In the absence of a firm link between individual meteorites and their asteroidal parent bodies, asteroids are typically characterized only by their light reflection properties, and grouped accordingly into classes. On 6 October 2008, a small asteroid was discovered with a flat reflectance spectrum in the 554-995 nm wavelength range, and designated 2008 TC(3) (refs 4-6). It subsequently hit the Earth. Because it exploded at 37 km altitude, no macroscopic fragments were expected to survive. Here we report that a dedicated search along the approach trajectory recovered 47 meteorites, fragments of a single body named Almahata Sitta, with a total mass of 3.95 kg. Analysis of one of these meteorites shows it to be an achondrite, a polymict ureilite, anomalous in its class: ultra-fine-grained and porous, with large carbonaceous grains. The combined asteroid and meteorite reflectance spectra identify the asteroid as F class, now firmly linked to dark carbon-rich anomalous ureilites, a material so fragile it was not previously represented in meteorite collections.

  1. Dynamic resistance of a high-Tc superconducting flux pump

    NASA Astrophysics Data System (ADS)

    Jiang, Zhenan; Hamilton, K.; Amemiya, Naoyuki; Badcock, R. A.; Bumby, C. W.

    2014-09-01

    Superconducting flux pumps enable large currents to be injected into a superconducting circuit, without the requirement for thermally conducting current leads which bridge between the cryogenic environment and room temperature. In this work, we have built and studied a mechanically rotating flux pump which employs a coated conductor high-Tc superconducting (HTS) stator. This flux pump has been used to excite an HTS double pancake coil at 77 K. Operation of the flux pump causes the current within the superconducting circuit to increase over time, before saturating at a limiting value. Interestingly, the superconducting flux pump is found to possess an effective internal resistance, Reff, which varies linearly with frequency, and is two orders of magnitude larger than the measured series resistance of the soldered contacts within the circuit. This internal resistance sets a limit for the maximum achievable output current from the flux pump, which is independent of the operating frequency. We attribute this effect to dynamic resistance within the superconducting stator wire which is caused by the interaction between the DC transport current and the imposed alternating magnetic field. We provide an analytical expression describing the output characteristics of our rotating flux pump in the high frequency limit, and demonstrate that it describes the time-dependent behavior of our experimental circuit. Dynamic resistance is highlighted as a generic issue that must be considered when optimizing the design of an HTS flux pump.

  2. Bosonization Theorem and a Model of High-Tc Superconductor.

    NASA Astrophysics Data System (ADS)

    Ren, Hai-Cang

    1996-03-01

    For a purely fermionic system on a lattice, there exists a different, but well defined system on the same lattice, consisting both of bona fide fermions and bosons with an interaction depending on a parameter G characterizing on-site repulsion between particles(R. Friedberg, T. D. Lee and H. C. Ren, Phys. Rev. B50, 10190 (1994).). The energy spectrum and the scattering matrix of the former are identical to those in the finite-energy sector of the latter in the hard-core limit, G→∞. This theorem is particularly useful for the description of a fermionic system whose low-lying spectrum consists of bosonic resonances. We argue that the high-Tc superconductors belong to this category and the long-range order in the superphase can be identified with the condensation of resonance bosons. A short coherence length, results from μSR experiments, measurements of the Hall number and the anomalous behavior of H_c2 near T=0 can be understood in terms of this resonance-boson model(R. Friedberg, T. D. Lee and H. C. Ren, Phys. Rev. B42, 4122 (1990).). We have also examined the possibility of a bosonic d-wave resonance(O.Tchernyshyov, A.S.Blaer and H.Ren, in the current Proceedings.). In this case, the bosonization theorem predicts coexistence of an s-wave bosonic condensate and a d-wave gap parameter for fermions.

  3. The impact and recovery of asteroid 2008 TC3

    NASA Astrophysics Data System (ADS)

    Jenniskens, P.; Shaddad, M. H.; Numan, D.; Elsir, S.; Kudoda, A. M.; Zolensky, M. E.; Le, L.; Robinson, G. A.; Friedrich, J. M.; Rumble, D.; Steele, A.; Chesley, S. R.; Fitzsimmons, A.; Duddy, S.; Hsieh, H. H.; Ramsay, G.; Brown, P. G.; Edwards, W. N.; Tagliaferri, E.; Boslough, M. B.; Spalding, R. E.; Dantowitz, R.; Kozubal, M.; Pravec, P.; Borovicka, J.; Charvat, Z.; Vaubaillon, J.; Kuiper, J.; Albers, J.; Bishop, J. L.; Mancinelli, R. L.; Sandford, S. A.; Milam, S. N.; Nuevo, M.; Worden, S. P.

    2009-03-01

    In the absence of a firm link between individual meteorites and their asteroidal parent bodies, asteroids are typically characterized only by their light reflection properties, and grouped accordingly into classes. On 6 October 2008, a small asteroid was discovered with a flat reflectance spectrum in the 554-995nm wavelength range, and designated 2008 TC3 (refs 4-6). It subsequently hit the Earth. Because it exploded at 37km altitude, no macroscopic fragments were expected to survive. Here we report that a dedicated search along the approach trajectory recovered 47 meteorites, fragments of a single body named Almahata Sitta, with a total mass of 3.95kg. Analysis of one of these meteorites shows it to be an achondrite, a polymict ureilite, anomalous in its class: ultra-fine-grained and porous, with large carbonaceous grains. The combined asteroid and meteorite reflectance spectra identify the asteroid as F class, now firmly linked to dark carbon-rich anomalous ureilites, a material so fragile it was not previously represented in meteorite collections.

  4. Diversification of 99Mo/99mTc separation: non–fission reactor production of 99Mo as a strategy for enhancing 99mTc availability.

    PubMed

    Pillai, Maroor R A; Dash, Ashutosh; Knapp, Furn F Russ

    2015-01-01

    This paper discusses the benefits of obtaining (99m)Tc from non-fission reactor-produced low-specific-activity (99)Mo. This scenario is based on establishing a diversified chain of facilities for the distribution of (99m)Tc separated from reactor-produced (99)Mo by (n,γ) activation of natural or enriched Mo. Such facilities have expected lower investments than required for the proposed chain of cyclotrons for the production of (99m)Tc. Facilities can receive and process reactor-irradiated Mo targets then used for extraction of (99m)Tc over a period of 2 wk, with 3 extractions on the same day. Estimates suggest that a center receiving 1.85 TBq (50 Ci) of (99)Mo once every 4 d can provide 1.48-3.33 TBq (40-90 Ci) of (99m)Tc daily. This model can use research reactors operating in the United States to supply current (99)Mo needs by applying natural (nat)Mo targets. (99)Mo production capacity can be enhanced by using (98)Mo-enriched targets. The proposed model reduces the loss of (99)Mo by decay and avoids proliferation as well as waste management issues associated with fission-produced (99)Mo.

  5. Tracheal blood flow and luminal clearance of [sup 99m][Tc]-DTPA in sheep

    SciTech Connect

    Hanafi, Z.; Corfield, D.R.; Webber, S.E.; Widdicombe, J.G. )

    1992-10-01

    Tracheal blood flow and [sup 99m][Tc]-labeled diethylenetriamine pentaacetic acid (DTPA) clearance were measured in the sheep trachea in vivo. The tracheal arteries were isolated and perfused. An isolated segment of tracheal lumen was filled with Krebs-Henseleit solution containing [sup 99m][Tc]-DTPA, and radioactivity was measured in blood from a catheterized tracheal vein. Infusions at constant pressure of methacholine (n=5), albuterol (n=6), and histamine (n=5) increased arterial inflow and venous outflow but decreased [sup 99m][Tc]-DTPA output and concentration. Phenylephrine (n=9) decreased arterial inflow and venous outflow but increased [sup 99m][Tc]-DTPA output and concentration. When the tracheal arteries were initially perfused at constant flow and the flow rate was then changed, 50% increases in flow (n=5) increased perfusion pressure and venous outflow but decreased [sup 99m][Tc]-DTPA output and concentration. Decreases in flow of 50% (n=3) and 100% (n=10) decreased perfusion pressure and venous outflow but increased [sup 99m][Tc]-DTPA output and concentration. Infusion of the same drugs at constant flow produced significant changes in perfusion pressure but no significant changes in venous outflow or, except for histamine, in [sup 99m][Tc]-DTPA output. Thus [sup 99m][Tc]-DTPA output was inversely related to both mechanically and drug-induced changes in tracheal blood flow but, except for histamine, was not directly affected by the drugs. The results may be due to redistribution of blood between collateral circuits and altered interstitial fluid volume affecting [sup 99m][Tc]-DTPA transport across the interstitium. 24 refs., 6 figs., 3 tabs.

  6. 99Mo/(99m)Tc separation: an assessment of technology options.

    PubMed

    Dash, Ashutosh; Knapp, F F Russ; Pillai, M R A

    2013-02-01

    Several strategies for the effective separation of (99m)Tc from (99)Mo have been developed and validated. Due to the success of column chromatographic separation using acidic alumina coupled with high specific activity fission (99)Mo (F (99)Mo) for production of (99)Mo/(99m)Tc generators, however, most technologies until recently have generated little interest. The reduced availability of F (99)Mo and consequently the shortage of (99)Mo/(99m)Tc column generators in the recent past have resurrected interest in the production of (99)Mo as well as (99m)Tc by alternate routes. Most of these alternative production processes require separation techniques capable of providing clinical grade (99m)Tc from low specific activity (99)Mo or irradiated Mo targets. For this reason there has been renewed interest in alternate separation routes. This paper reviews the reported separation technologies which include column chromatography, solvent extraction, sublimation and gel systems that have been traditionally used for the fabrication of (99)Mo/(99m)Tc generator systems. The comparative advantage, disadvantage, and technical challenges toward adapting the emerging requirements are discussed. New developments such as solid-phase column extraction, electrochemical separation, extraction chromatography, supported liquid membrane (SLM) and thermochromatographic techniques are also being evaluated for their potential application in the changed scenario of providing (99m)Tc from alternate routes. Based on the analysis provided in this review, it appears that some proven separation technologies can be quickly resurrected for the separation of clinical grade (99m)Tc from macroscopic levels of reactor or cyclotron irradiated molybdenum targets. Furthermore, emerging technologies can be developed further to respond to the expected changing modes of (99m)Tc production.

  7. TC-5214 (S-(+)-mecamylamine): a neuronal nicotinic receptor modulator with antidepressant activity.

    PubMed

    Lippiello, Patrick M; Beaver, Jessica S; Gatto, Gregory J; James, John W; Jordan, Kristen G; Traina, Vincent M; Xie, Jianxun; Bencherif, Merouane

    2008-01-01

    Both clinical and preclinical data support a potential therapeutic benefit of modulating the activity of CNS neuronal nicotinic receptors (NNRs) to treat depression and anxiety disorders. Based on the notion that the depressive states involve hypercholinergic tone, we have examined the potential palliative role of NNR antagonism in these disorders, using TC-5214 (S-(+) enantiomer of mecamylamine), a noncompetitive NNR antagonist. TC-5214 demonstrated positive effects in a number of animal models of depression and anxiety. TC-5214 was active in the forced swim test in rats (minimum effective dose (MED)=3 mg/kg i.p.), a classical depression model. It was also active in the behavioral despair test in mice (0.1-3.0 mg/kg i.p.), another model of depression. In the social interaction paradigm in rats, a model of generalized anxiety disorder (GAD), TC-5214 was active at a dose of 0.05 mg/kg s.c. In the light/dark chamber paradigm in rats, a model of GAD and phobia, TC-5214 was also active at a dose of 0.05 mg/kg s.c. Although TC-5214 shows modest selectivity among NNR subtypes, the antidepressant and anxiolytic effects seen in these studies are likely attributable to antagonist effects at the alpha4beta2 NNRs. This is supported by the observation of similar effects with alpha4beta2-selective partial agonists such as cytisine and with alpha4beta2-selective antagonists such as TC-2216. TC-5214 was well tolerated in acute and chronic toxicity studies in mice, rats, and dogs, showed no mutagenicity and displayed safety pharmacology, pharmacokinetic and metabolic profiles appropriate for therapeutic development. Overall, the results support a novel nicotinic cholinergic antagonist mechanism for antidepressant and anxiolytic effects and highlight the potential of NNR antagonists such as TC-5214 as therapeutics for the treatment of anxiety and depression.

  8. Popliteal cysts and deep venous thrombosis: Tc-99m red blood cell venography

    SciTech Connect

    Littlejohn, G.O.; Brand, C.A.; Ada, A.; Wong, C.

    1985-04-01

    Thirty-four patients who clinically were suspected of having deep venous thrombosis (DVT) underwent Tc-99m red blood cell (RBC) venography followed by contrast venography. The sensitivity (88%) and specificity (94%) of Tc-99m RBC venography of DVT confirmed findings of previous studies. Twenty-four patients who had proved popliteal cysts and swollen calves also were examined using Tc-99m RBC venography. Large cysts showed lack of DVT features, photon deficient cold areas in the popliteal fossa, and diversion of venous flow around the photon deficient area. These features were seen in 25% of the study population (six patients), and assisted in the distinction between the two conditions.

  9. Etiology of amyloidosis determines myocardial 99mTc-DPD uptake in amyloidotic cardiomyopathy.

    PubMed

    Longhi, Simone; Bonfiglioli, Rachele; Obici, Laura; Gagliardi, Christian; Milandri, Agnese; Lorenzini, Massimiliano; Guidalotti, Pier Luigi; Merlini, Giampaolo; Rapezzi, Claudio

    2015-05-01

    Tc-DPD (Tc-3,3-diphosphono-1,2-propanodicarboxylic acid) has a high affinity for transthyretin (TTR)-infiltrated myocardium, allowing a differential diagnosis with light chain cardiac amyloidosis and other nonamyloidotic cardiomyopathies with a hypertrophic phenotype, in which myocardial tracer uptake is low or absent. Myocardial bone tracer uptake in the rarer forms of amyloidosis (eg, apolipoprotein-related) has been rarely studied. We present 4 cases of cardiac amyloidosis that underwent Tc-DPD scintigraphy; myocardial DPD uptake was present in patients with ATTR, wtTTR and apolipoprotein AI and negative in cases with AL and apolipoprotein AII-related disease.

  10. Use of 99mTc-mercaptoacetyltriglycine to evaluate renal function in horses.

    PubMed

    Woods, P R; Drost, W T; Clarke, C R; Rodebush, C J

    2000-01-01

    Ten healthy horses were injected intravenously with 99mTc-MAG3 and the disappearance of radioactivity from the blood was measured. The total body clearance (Cl(B)) and elimination half-life (t1/2(beta)) were 7.9 +/- 1.5 ml/kg/minute and 32.8 +/- 4.1 minutes, respectively. The disappearance of 99mTc-MAG3 from the blood of 2 horses with compromised renal function was also measured. The data suggest that 99mTc-MAG3 is a useful and clinically applicable radiopharmaceutical for measurement of effective renal blood flow in the horse.

  11. Assessment of Using 99Mo and 99mTc Isotopes in Kuwait Medical Sector.

    PubMed

    Ali, Naser

    2016-04-01

    The Ministry of Health (MOH) in the state of Kuwait currently depends on importing the radioisotope molybdenum (Mo) in its isotopic form (Mo) to fulfill its demands. The present study was conducted on all nuclear medicine departments in the state of Kuwait. Daily, weekly, and monthly data were analyzed to statistically determine the current and future demands for the isotope Tc. This analysis was performed by collecting and analyzing data on MOH consumption of Tc for different diagnostic applications. The overall results indicate a partial decrease of 1.012% in the overall total demand for Tc up to the year 2018 for the state of Kuwait.

  12. 14N nuclear quadrupole resonance of p-nitrotoluene using a high-Tc rf SQUID

    NASA Astrophysics Data System (ADS)

    He, D. F.; Tachiki, M.; Itozaki, H.

    2007-03-01

    Using a high-Tc radio-frequency superconducting quantum interference device (rf SQUID), we successfully detected nuclear quadrupole resonance (NQR) at about 887 kHz for 14N in p-nitrotoluene (PNT). A normal metal transformer made of copper wire was used to improve the sensitivity of the high-Tc rf SQUID and pulse-controlled rf switches and cross diodes were inserted in the transformer to reduce the influence of the strong excitation field. The preliminary results for NQR detection using the high-Tc SQUID had a similar signal-to-noise ratio to that of using a low noise preamplifier.

  13. /sup 99m/Tc-aprotinin: A new tracer for kidney morphology and function

    SciTech Connect

    Bianchi, C.; Donadio, C.; Tramonti, G.; Lorusso, P.; Bellitto, L.; Lunghi, F.

    1984-01-01

    Aprotinin (Ap), a low molecular weight polyeptide (6500 dalton), is a protease inhibitor which is electively and stably accumulated in the kidney. In 112 adult patients, with either uni- or bilateral renal disease with different degrees of renal impairment (from normal GFR to advanced renal failure), renal scans were performed by means of Ap labelled with /sup 99m/Tc. Highly satisfactory renal scans were obtained in all patients. In 20 patients with renal failure (serum creatinine 1.8 - 8.5 mg/dl, mean 4.7) a comparison was made of the renal scans obtained with /sup 99m/Tc-Ap and with /sup 99m/Tc-DMSA. /sup 99m/Tc-Ap was slightly better than /sup 99m/Tc-DMSA, especially in patients with far advanced renal failure. Some aspects of the pharmacokinetics of /sup 99m/Tc-Ap were studied in 72 cases. In 22 of these patients plasma clearance of /sup 99m/Tc-Ap was determined by the single injection method using a two-compartment model. In patients with GFR>90 ml/min plasma cl of /sup 99m/Tc-Ap was 67.6 +- 8.4 SD ml/min. A good correlation was observed between plasma clearance of /sup 99m/Tc-Ap and GFR (r = 0.74). After i.v. injection /sup 99m/Tc-Ap was stably fixed by the kidney. Renal radioactivity remained stable between the 2nd and the 8th hour after the injection. Urinary excretion of radioactivity measured in 35 patients in the first and in the second 2-hour interval after i.v. injection of /sup 99m/Tc-Ap was negligible in all patients (2.7 +- 1.5 SD percent of the dose in the fist 2 hours; 2.8 +- 1.4 SD between the 2nd and the 4th hour). Conclusions. /sup 99m/Tc-Ap is an excellent agent for renal imaging. It also seems promising for renal function studies.

  14. 99mTc-DMSA scanning to diagnose pyelonephritic scarring in children

    SciTech Connect

    Kogan, B.A.; Kay, R.; Wasnick, R.J.; Carty, H.

    1983-06-01

    99mTechnetium-labeled dimercaptosuccinic acid (99mTc-DMSA) scanning provides superior quality images of renal parenchymal detail, which makes it highly sensitive for the diagnosis of pyelonephritic scarring. Unlike most other imaging techniques, radionuclide scanning is not affected by bowel gas or bony structures overlying the kidneys. This makes it particularly useful in children. Furthermore, renal scarring can be demonstrated by 99mTc-DMSA even before the classic gross anatomic and radiologic changes are present. The use of 99mTc-DMSA scanning in over 300 children has demonstrated its benefits and advantages over standard radiographic techniques.

  15. Conveniently prepared Tc-99m resin for semisolid gastric emptying studies

    SciTech Connect

    Wirth, N.; Shapiro, B.; Nakajo, M.; Coffey, J.L.; Eckhauser, F.; Owyang, C.

    1983-06-01

    A polystyrene resin, suitable for semi-solid gastric emptying studies, was rapidly (<20 min) and coveniently prepared using commercially available reagents. Using the outlined procedure, Chelex-100 resin bound Tc-99m with greater than 98% labeling efficiency. The resulting Tc-99m Chelex-100 resin demonstrated excellent in vitro and in vivo stability. The clinical application of Tc-99m Chelex-100 resin, mixed with oatmeal, was tested in normal subjects and in various patient groups, including diabetic autonomic neuropathy, pyloric obstruction, postoperative dumping syndrome, and morbidly obese patients before and after gastroplasty.

  16. A conveniently prepared Tc-99m resin for semisolid gastric emptying studies

    SciTech Connect

    Wirth, N.; Swanson, D.; Shapiro, B.; Nakajo, M.; Coffey, J.L.; Eckhauser, F.; Owyang, C.

    1983-06-01

    A polystyrene resin, suitable for semi-solid gastric emptying studies, was rapidly (less than 20 min) and conveniently prepared using commercially available reagents. Using the outlined procedure, Chelex-100 resin bound Tc-99m with greater than 98% labeling efficiency. The resulting Tc-99m Chelex-100 resin demonstrated excellent in vitro and in vivo stability. The clinical application of Tc-99m Chelex-100 resin, mixed with oatmeal, was tested in normal subjects and in various patient groups, including diabetic autonomic neuropathy, pyloric obstruction, postoperative dumping syndrome, and morbidly obese patients before and after gastroplasty.

  17. Predicting Single-Layer Technetium Dichalcogenides (TcX₂, X = S, Se) with Promising Applications in Photovoltaics and Photocatalysis.

    PubMed

    Jiao, Yalong; Zhou, Liujiang; Ma, Fengxian; Gao, Guoping; Kou, Liangzhi; Bell, John; Sanvito, Stefano; Du, Aijun

    2016-03-02

    One of the least known compounds among transition metal dichalcogenides (TMDCs) is the layered triclinic technetium dichalcogenides (TcX2, X = S, Se). In this work, we systematically study the structural, mechanical, electronic, and optical properties of TcS2 and TcSe2 monolayers based on density functional theory (DFT). We find that TcS2 and TcSe2 can be easily exfoliated in a monolayer form because their formation and cleavage energy are analogous to those of other experimentally realized TMDCs monolayer. By using a hybrid DFT functional, the TcS2 and TcSe2 monolayers are calculated to be indirect semiconductors with band gaps of 1.91 and 1.69 eV, respectively. However, bilayer TcS2 exhibits direct-bandgap character, and both TcS2 and TcSe2 monolayers can be tuned from semiconductor to metal under effective tensile/compressive strains. Calculations of visible light absorption indicate that 2D TcS2 and TcSe2 generally possess better capability of harvesting sunlight compared to single-layer MoS2 and ReSe2, implying their potential as excellent light-absorbers. Most interestingly, we have discovered that the TcSe2 monolayer is an excellent photocatalyst for splitting water into hydrogen due to the perfect fit of band edge positions with respect to the water reduction and oxidation potentials. Our predictions expand the two-dimensional (2D) family of TMDCs, and the remarkable electronic/optical properties of monolayer TcS2 and TcSe2 will place them among the most promising 2D TMDCs for renewable energy application in the future.

  18. Intrinsic MyD88-Akt1-mTOR Signaling Coordinates Disparate Tc17 and Tc1 Responses during Vaccine Immunity against Fungal Pneumonia.

    PubMed

    Nanjappa, Som Gowda; Hernández-Santos, Nydiaris; Galles, Kevin; Wüthrich, Marcel; Suresh, M; Klein, Bruce S

    2015-09-01

    Fungal infections have skyrocketed in immune-compromised patients lacking CD4+ T cells, underscoring the need for vaccine prevention. An understanding of the elements that promote vaccine immunity in this setting is essential. We previously demonstrated that vaccine-induced IL-17A+ CD8+ T cells (Tc17) are required for resistance against lethal fungal pneumonia in CD4+ T cell-deficient hosts, whereas the individual type I cytokines IFN-γ, TNF-α and GM-CSF, are dispensable. Here, we report that T cell-intrinsic MyD88 signals are crucial for these Tc17 cell responses and vaccine immunity against lethal fungal pneumonia in mice. In contrast, IFN-γ+ CD8+ cell (Tc1) responses are largely normal in the absence of intrinsic MyD88 signaling in CD8+ T cells. The poor accumulation of MyD88-deficient Tc17 cells was not linked to an early onset of contraction, nor to accelerated cell death or diminished expression of anti-apoptotic molecules Bcl-2 or Bcl-xL. Instead, intrinsic MyD88 was required to sustain the proliferation of Tc17 cells through the activation of mTOR via Akt1. Moreover, intrinsic IL-1R and TLR2, but not IL-18R, were required for MyD88 dependent Tc17 responses. Our data identify unappreciated targets for augmenting adaptive immunity against fungi. Our findings have implications for designing fungal vaccines and immune-based therapies in immune-compromised patients.

  19. 99mTc-Tetraethylenepentamine-Folate--a new 99mTc-based folate derivative for the detection of folate receptor positive tumors: synthesis and biological evaluation.

    PubMed

    Panwar, Puja; Shrivastava, Vibha; Tandon, Vibha; Mishra, Pushpa; Chuttani, Krishna; Sharma, Rakesh Kumar; Chandra, Ramesh; Mishra, Anil K

    2004-10-01

    A new radiopharmaceutical, 99mTc-Tetraethylenepentamine(TEPA)-Folate has been synthesized introducing TEPA to the gamma-carboxyl group of folic acid. This binds with 99mTc high efficiency at ambient temperature. The resulting 99mTc-N5-Folate is stable under physiological conditions at least for 24 h after radiocomplexation. TEPA is a known open chain pentamine (N5) chelator, its four-nitrogen act as the binding site for 99mTc. The folate membrane receptor binding of the 99mTc-TEPA-Folate by established human tumor cell lines (KB, U-87MG and MDA-MB-468) showed Kd in microM range in normal DMEM (10% serum, 10 microM folic acid). The blood kinetic studies showed more than 70% clearance within five minutes from the circulation. The KB cell line tumors in mice were readily identifiable in the gamma images and revealed major accumulation of radiotracer in liver, kidneys and intestines. High tumor uptake was shown in the tumor bearing nude mice; tumorto-blood ratios reached 2.68 +/- 0.52 and 5.5 +/- 1.47 at 1 and 4 h after post injection respectively. Surviving fractions as obtained in clonogenic assay were 1.02 +/- 0.07 and 1.03 +/- 0.05 in U-87MG and MDA-MB-468 cell lines respectively. The 99mTc-N5-Folate conjugate have promising utility as a receptor specific radiopharmaceutical for imaging neoplastic tissues known to over express folate-binding protein.

  20. Crossed Fused Renal Ectopia: Presentations on 99mTc-MAG3 Scan, 99mTc-DMSA SPECT, and Multidetector CT.

    PubMed

    Moon, Eun Ha; Kim, Min-Woo; Kim, Young Jun; Sun, In O

    2015-10-01

    Crossed renal ectopia is an uncommon developmental anomaly in which both kidneys are located on the same side of the body. The present case describes a 20-year-old man who underwent the military entrance physical examination. The ultrasound showed the right kidney in normal site with slightly increased size, but the left kidney was not identified. Tc-MAG3 scan showed a single kidney with 2 ureters, and the orifices of the ureters were connected at both sides of bladder. Tc-DMSA SPECT and contrast-enhanced multidetector CT were performed and revealed crossed fused renal ectopia.

  1. U.S. TAG for ISO/TC43 Acoustics and IEC/TC29 Electroacoustics (Minutes for the Accredited Standards Committee on Acoustics, S1)

    DTIC Science & Technology

    1991-05-02

    NOTE At the S3 meeting, Mr. Grason and Ms. Wilber also indicated their probable participation in the ISO/TC 43 meetings. 7. Review of Standards more...A. Wilber G. S. K. Wong R. W. Young S1/347 ATTACHMENT C-6 Not for reproduction 29(USA Original: English March 1990 INTERNATIONAL ELECTROTECHNICAL...Nielsen, the Secretary of TC 29, with copy to the Central Office, by April 15, 1991. encl. cc: A. V. Brenig R. L. Grason L. A. Wilber Not for

  2. High-Tc SQUID Magnetometers for Industrial Applications

    NASA Astrophysics Data System (ADS)

    Diiorio, Mark; Yang, Kai-Yueh; Yoshizumi, Shozo; Haupt, Steven; Haran, Don; Koch, Roger; Lathrop, Dan; Trammel, Hoke

    1998-03-01

    We have developed high-Tc SQUID magnetometers for use in a variety of industrial applications. Relatively inexpensive direct-coupled magnetometers have been developed for low-frequency applications including fetal-magnetocardiography. A manufacturable process has been developed to reproducibly fabricate high-resistance (up to 6 Ω) SNS step-edge junctions with YBa_2Cu_3O_7-x as the superconductor and Ag-Au alloy as the normal metal. Magnetic field sensitivities at 77K of 22 ft/Hz^1/2 at 1 KHz and 32 ft/Hz^1/2 at 1 Hz have been achieved in a well-shielded laboratory environment. Current effort is focused on operation in an unshielded environment using flux dams(Milliken et al. Appl. Phys. Lett. 71 1857 (1997)) in conjunction with narrow superconducting pickup coils placed in parallel. An integrated magnetometer process has also been optimized for use in high-frequency applications. The integrated megnetometer utilizes two layers of YBa_2Cu_3O_7-x and one layer of deposited SrTiO_3, all on the same 24 mm x 5 mm substrate. The applications under development include the detection of the explosive material in non-metallic land mines using nuclear quadrupole resonance as well as the non-destructive evaluation of non-metallic composites using nuclear magnetic resonance. For operation in the MHz regime, these applications demand a high quality insulator layer and a robust SQUID that can withstand high current transients.

  3. Fermi surface reconstruction in high-Tc superconductors

    NASA Astrophysics Data System (ADS)

    Taillefer, Louis

    2009-03-01

    The recent observation of quantum oscillations in underdoped high-Tc superconductors (1), combined with their negative Hall coefficient at low temperature (2), reveals that the Fermi surface of hole-doped cuprates includes a small electron pocket. This strongly suggests that the large hole Fermi surface characteristic of the overdoped regime undergoes a reconstruction caused by the onset of some order which breaks translational symmetry. Here we consider the possibility that this order is ``stripe'' order, a form of combined charge / spin modulation observed most clearly in materials like Eu- doped and Nd-doped LSCO. In these materials, the onset of stripe order coincides with major changes in transport properties (3), providing strong evidence that stripe order is indeed the cause of Fermi-surface reconstruction. We identify the critical doping where this reconstruction occurs and show that the temperature dependence of transport coefficients at that doping is typical of metals at a quantum critical point (4). We discuss an interpretation of the pseudogap as a fluctuating precursor of the stripe-ordered phase.This work was performed in collaboration with L. Balicas, D.A. Bonn, J. Chang, O. Cyr-Choinière, R. Daou, N. Doiron- Leyraud, W.N. Hardy, N.E. Hussey, F. Lalibert'e, D. LeBoeuf, S.Y. Li, R. Liang, C. Proust, H. Takagi, and J.S. Zhou.(1) N. Doiron-Leyraud et al., Nature 447, 565 (2007).(2) D. LeBoeuf et al., Nature 450, 533 (2007).(3) R. Daou et al., Nature Physics, in press (DOI 10.1038/nphys1109); http://arXiv.org/abs/0806.2881.(4) R. Daou et al., to be published; http://arXiv.org/abs/0810.4280.

  4. The Impact Trajectory of Asteroid 2008 TC3

    NASA Astrophysics Data System (ADS)

    Chodas, Paul; Chesley, S.; Yeomans, D.

    2009-09-01

    On October 6, 2008, the small newly discovered near-Earth asteroid 2008 TC3 was found to be on an Earth-impacting trajectory, with impact less than 20 hours away. This was the first ever predicted impact of a near-Earth object. Fortunately, it was immediately clear that the object was only a few meters in size and would almost certainly break up when it entered the Earth's tmosphere. We review the pre-impact orbit computations and predictions, the post-impact reconstructions of the trajectory, and the trajectory geometry. The first prediction of impact was made by the Minor Planet Center (MPC), which quickly made the discovery and subsequent follow-up observations available to the astronomical community and contacted both the NASA/JPL Near-Earth Object Program Office and NASA headquarters. Within an hour of receiving the initial data set, JPL predicted that the atmospheric entry would occur over northern Sudan around 02:46 UT on October 7. As the day progressed and more data arrived from the MPC, the impact prediction accuracy continued to improve. A press release was issued at 21:30 UT announcing the predicted impact later that night. Detections of the actual atmospheric impact event suggested that it was an airburst explosion at an altitude of 37 km with an energy equivalent to about one kiloton of TNT explosives. The airburst occurred at 02:45:45 UT at about 32.2 East longitude and 20.8 North latitude, matching the final impact predictions to within 0.2 s in time and 1.5 km in position.

  5. IL-4 inhibits VLA-4 expression on Tc1 cells resulting in poor tumor infiltration and reduced therapy benefit.

    PubMed

    Sasaki, Kotaro; Pardee, Angela D; Okada, Hideho; Storkus, Walter J

    2008-10-01

    We and others have previously demonstrated that IL-4-dependent Tc2 are inferior to Tc1-effector CD8+ T cells in regulating tumor progression in vivo. This functional disparity relates, in part, to the comparatively poor ability of Tc2 to migrate into diseased tissues. We now show that IL-4 treatment of committed Tc1 cells promotes the selective loss in the expression of very-late antigen (VLA)-4, without impacting the Tc1 cytokine production profile, cytotoxic activity, or expression of alternate cell surface markers. Down-regulation of VLA-4 expression on Tc1 cells was unique to treatment with IL-4 (i.e. Tc1IL-4) and did not occur in the presence of the Type-2 cytokine IL-13 or the regulatory cytokines IL-10 or TGF-beta. Notably, the inhibitory effects of IL-4 on Tc1 expression of VLA-4 could be blocked by the presence of IL-12, but not IFN-gamma. Predictably, Tc1IL-4 (but not Tc1 control) cells adhere poorly to plate-bound VCAM-1-Fc fusion protein and fail to be co-stimulated by VCAM-1 in vitro. They were also markedly impaired in their ability to traffic into intracranial melanoma lesions after adoptive transfer, yielding inferior therapeutic benefit to tumor-bearing mice. These results suggest a novel suppressive mechanism for IL-4 that limits Tc1 efficacy via preventing their recruitment into tumors.

  6. IL-4 inhibits VLA-4 expression on Tc1 cells resulting in poor tumor infiltration and reduced therapy benefit

    PubMed Central

    Sasaki, Kotaro; Pardee, Angela D.; Okada, Hideho; Storkus, Walter J.

    2009-01-01

    We and others have previously demonstrated that IL-4-dependent Tc2 are inferior to Tc1 effector CD8+ T cells in regulating tumor progression in vivo. This functional disparity relates, in part, to the comparatively poor ability of Tc2 to migrate into diseased tissues. We now show that IL-4 treatment of committed Tc1 cells promotes the selective loss in expression of Very-Late Antigen (VLA)-4, without impacting the Tc1 cytokine production profile, cytotoxic activity, or expression of alternate cell surface markers. Down-regulation of VLA-4 expression on Tc1 cells was unique to treatment with IL-4 (i.e. Tc1IL-4), and did not occur in the presence of the Type 2 cytokine IL-13 or the regulatory cytokines IL-10 or TGF-β. Notably, the inhibitory effects of IL-4 on Tc1 expression of VLA-4 could be blocked by the presence of IL-12, but not IFN-γ. Predictably, Tc1IL-4 (but not Tc1 control) cells adhere poorly to plate-bound VCAM-1-Fc fusion protein and fail to be co-stimulated by VCAM-1 in vitro. They were also markedly impaired in their ability to traffic into intracranial melanoma lesions after adoptive transfer, yielding inferior therapeutic benefit to tumor-bearing mice. These results suggest a novel suppressive mechanism for IL-4 that limits Tc1 efficacy via preventing their recruitment into tumors. (200 words) PMID:18958887

  7. Methods for MAG3 conjugation and 99mTc radiolabeling of biomolecules.

    PubMed

    Wang, Yi; Liu, Guozheng; Hnatowich, Donald J

    2006-01-01

    The chelator mercaptoacetyltriglycine (MAG3) forms a single stable chelate with technetium-99m (99mTc) oxotechnetate. The bifunctional N-hydroxysuccinimidyl ester of mercaptoacetyltriglycine with S-acetyl protection of the sulfhydryl group may be used to conjugate MAG3 to primary amine functionalized biomolecules for the purpose of radiolabeling with 99mTc for gamma detection or single photon emission computed tomography imaging (SPECT). We report here an improved MAG3 conjugation and 99mTc radiolabeling method capable of generating high radiochemical yield and high specific radioactivity. Post-labeling purification will not be needed if the protocol is followed as presented. Apart from the preparation of reagents, the conjugation and purification requires about 4 h, while the labeling with 99mTc requires about an additional 30 min.

  8. Bioreduction of Fe-bearing clay minerals and their reactivity toward pertechnetate (Tc-99)

    SciTech Connect

    Bishop, Michael E.; Dong, Hailiang; Kukkadapu, Ravi K.; Liu, Chongxuan; Edelmann, Richard E.

    2011-07-01

    99Technetium (99Tc) is a fission product of uranium-235 and plutonium-239 and poses a high environmental hazard due to its long half-life (t1/2 = 2.13 x 105 y), abundance in nuclear wastes, and environmental mobility under oxidizing conditions [i.e., Tc(VII)]. Under reducing conditions, Tc(VII) can be reduced to insoluble Tc(IV). Ferrous iron [Fe(II)], either in aqueous form or in mineral form, has been used to reduce Tc(VII) to Tc(IV). However, the reactivity of Fe(II) from clay minerals, other than nontronite, toward immobilization of Tc(VII) and its role in retention of reduced Tc(IV) have not been investigated. In this study the reactivity of a suite of clay minerals toward Tc(VII) reduction and immobilization was evaluated. The clay minerals chosen for this study included five members in the smectite-illite (S-I) series, (montmorillonite, nontronite, rectorite, mixed layered I-S, and illite), chlorite, and palygorskite. Fe-oxides were removed from these minerals with a modified dithionite-citrate-bicarbonate (DCB) procedure. The total Fe content of these clay minerals, after Fe-oxide removal, ranged from 0.7 to 30.4% by weight, and the Fe(III)/Fe(total) ratio ranged from 44.9 to 98.5%. X-ray diffraction (XRD) and Mössbauer spectroscopy results showed that after Fe oxide removal the clay minerals were free of Fe-oxides. Scanning electron microscopy (SEM) revealed that little dissolution occurred during the DCB treatment. Bioreduction experiments were performed in bicarbonate buffer (pH-7) with Fe(III) in the clay minerals as the sole electron acceptor, lactate as the sole electron donor, and Shewanella Putrifaciens CN32 cells as mediators. In select tubes, anthraquinone-2,6-disulfate (AQDS) was added as electron shuttle to facilitate electron transfer. The extent of Fe(III) bioreduction was the highest for chlorite (~43 wt%) and the lowest for palygorskite (~4.17 wt%). In the S-I series, NAu-2 was the most reducible (~31 %) and illite the least (~0.4 %). The

  9. Synthesis and biological assessment of folate-accepted developer (99m)Tc-DTPA-folate-polymer.

    PubMed

    Chen, Fei; Shao, Kejing; Zhu, Bao; Jiang, Mengjun

    2016-05-15

    A novel cancer-targetable folate-poly(2-hydroxyethyl methacrylate) (PFDH) copolymer containing DTPA segment was prepared by conventional chemical synthesis and labeled with (99m)Tc subsequently. The (99m)Tc-labled PFDH could be produced easily with high radiochemical yield of 91% and radiochemical purity of 95%. The LogP octanol-water value for the (99m)Tc-labled PFDH was -2.19 and the radiotracer was stable in phosphate-buffered saline and human serum for 2h (>95% in PBS or ∼90% in human serum). To investigate (99m)Tc-labled PFDH tumor targeting, the in vitro and in vivo stability, cell uptake, in vivo biodistribution, and SPECT imaging were evaluated, respectively. These preliminary results strongly suggest that the novel folate conjugated dendrimer maybe developed to be potential for delivery of therapeutic radionuclides.

  10. Tc-99m labeled leukocytes: preparation and use in identification of abscess and tissue rejection

    SciTech Connect

    Farid, N.A.; White, S.M.; Heck, L.L.; Van Hove, E.D.

    1983-09-01

    A simple and reproducible method for the preparation and labeling of leukocytes with Tc-99m has been developed. Leukocytes were separated from blood, incubated with stannous pyrophosphate, and then with 20-30 mCi (740-1110 MBq) of /sup 99m/TcO-4. In leukocytes separated from human blood, the labeling efficiency was 81% +/- 6% (n . 4). Experiments on dogs with abscesses showed accumulation of the Tc-99m-labeled leukocytes in the infected sites, indicating the viability of the labeled leukocytes. Additional studies showed that rat lymphocytes that were labeled with Tc-99m, using the same technique, localized in heart transplant tissue that was being rejected.

  11. Tc-99m labeled leukocytes: preparation and use in identification of abscess and tissue rejection

    SciTech Connect

    Farid, N.A.; White, S.M.; Heck, L.L.; Van Hove, E.D.

    1983-09-01

    A simple and reproducible method for the preparation and labeling of leukocytes with Tc-99m, has been developed. Leukocytes were separated from blood, incubated with stannous pyrophosphate, and then with 20-30 mCi (740-1110 M Bq) of /sup 99m/TcO/sub 4//sup -/. In leukocytes separated from human blood, the labeling efficiency was 81% +/- 6% (n=4). Experiments on dogs with abscesses showed accumulation of the Tc-99m-labeled leukocytes in the infected sites, indicating the viability of the labeled leukocytes. Additional studies showed that rat lymphocytes that were labeled with Tc-99m, using the same technique, localized in heart transplant tissue that was being rejected.

  12. Superior sagittal sinus thrombosis: assessment with Tc-99m labeled red blood cells

    SciTech Connect

    Front, D.; Israel, O.; Even-Sapir, E.; Feinsud, M.

    1986-02-01

    The diagnostic value of scintigraphy with technetium-99m labeled red blood cells (Tc-RBC) was assessed in 19 patients with clinical suggestion of superior sagittal sinus thrombosis (SSST). Comparison of Tc-RBC static images with dynamic flow studies in the brain showed a sensitivity of 100%, specificity of 86%, and accuracy of 94% for static studies and values of 87%, 20%, and 61%, respectively, for the flow studies. Tc-RBC scintigraphy enables direct visualization of the integrity of the superior sagittal sinus, whereas CT scanning shows various but nonspecific changes in the brain associated with SSST. Single-photon emission CT study using Tc-RBC, performed in six patients, appears to have potential in the diagnosis of SSST, allowing separation of vascular structures that are superimposed on the superior sagittal sinus in planar scintigraphy study.

  13. The Structure of Mesons Near Tc - the Qcd-Taro Collaboration -

    NASA Astrophysics Data System (ADS)

    Akemi, K.; Fujisaki, M.; Okuda, M.; Tago, Y.; Hashimoto, T.; Hioki, S.; Miyamura, O.; Matsufuru, H.; Nakamura, A.; de Forcrand, Ph.; Stamatescu, I. O.; Takaishi, T.

    We discuss problems related to the analysis of finite temperature 4-point correlators in the mesonic chanels. We present preliminary results on the pion wave function and dispersion law in quenched QCD at T ≃ 0.83TC.

  14. Preparation of the High-Tc Phase of Bi-Sr-Ca-Cu-O Superconductor

    NASA Astrophysics Data System (ADS)

    Endo, Utako; Koyama, Satoshi; Kawai, Tomoji

    1988-08-01

    Co-decomposition of mixed nitrates of Bi, Pb, Sr, Ca and Cu around 830°C under low oxygen pressure led to the formation of a high-Tc superconducting phase of Bi(Pb)-Sr-Ca-Cu-O with Tc(zero) at 107.5 K. A sample prepared by a conventional solid state reaction method under low oxygen pressure also showed the superconducting transition at 107.5 K. X-ray powder diffraction and magnetic susceptibility measurements on these samples revealed the high-Tc phase without 80 K or semiconducting phase. The reaction under low oxygen pressure has an effect to lower the temperature with broad ranges to render the high-Tc phase of the Bi-Sr-Ca-Cu-O.

  15. The Effect of Antiseptic on 99mTc-DMSA Scans.

    PubMed

    Firuzyar, Tahereh; Ghaedian, Tahereh

    2017-03-01

    Approximately 30 years ago, it has been suggested that chlorhexidine, which is used as antiseptic, can produce Tc colloid complex during Tc-dimercaptosuccinic acid (DMSA) preparation. However, in all cases of liver and spleen uptake in Tc-DMSA scan, it should still be kept in mind because of the introduction of new antiseptic brands with different formulation under various names. Our case is just a sample of this effect, which resulted from application of a new brand of antiseptic by technologists in our center that unintentionally led to low-quality Tc-DMSA scans for a period, and after restrict control of all other confounding factors in the preparation of kit, it was just resolved by changing antiseptic to ethanol.

  16. Incidental detection of gastrointestinal stromal tumor by Tc-99m MDP bone scan.

    PubMed

    Shepherd, Timothy M; Idakoji, Ibrahim A; Pampaloni, Miguel H

    2012-02-01

    This case demonstrates extraosseous 99m-technetium methylene diphosphonate (Tc-99m MDP) accumulation from a gastrointestinal stromal tumor. A 75-year-old woman underwent a temporal bone CT for conductive hearing loss that showed sclerosis in the right occipital condyle. Follow-up Tc-99m MDP bone scan for osseous metastases instead showed a mass-like extraosseous accumulation of Tc-99m MDP in the anterior left upper quadrant. Differential diagnoses included gastric cancer, lymphoma, metastatic melanoma, systemic hypercalcemia, or heterotopic mesenteric ossification. Contrast CT showed a well-circumscribed mass arising from the stomach, and subsequent pathology confirmed gastrointestinal stromal tumor. These tumors rarely can contain osteoclast-like giant cells and should be considered for extraosseous Tc-99m MDP accumulation.

  17. Visualization of cutaneous hemangioma with Tc-99m tagged red blood cells

    SciTech Connect

    Gordon, L.; Vujic, I.; Spicer, K.M.

    1981-10-01

    Scintigraphy with Tc-99m labeled red blood cells (RBCs) was used to evaluate a patient with a large cutaneous hemangioma. The usefulness of this procedure when combined with arteriography is discussed.

  18. Preparation and evaluation of (99m)Tc-DMSA lyophilized kit for renal imaging.

    PubMed

    Jan, Syed Umer; Abbass, Hafiz Ghulam

    2013-05-01

    Dimercaptosuccinic acid (DMSA) has been evaluated and used with technetium 99m ((99m)Tc) in imaging of kidneys. DMSA lyophilized kits were prepared and radiolabelled with (99m)Tc. Paper and thin-layer chromatography have been employed using various eluent systems for the radiochemical analysis, percentage labeling and binding capacity of (99m)Tc-DMSA. Female albino rabbits were used for this study. Biological data obtained after intravenous injection of radiolabelled DMSA to female albino rabbits revealed 32.42% uptake and long retention time in the kidneys. On the basis of animal biodistribution data, it is suggested that DMSA when labeled with (99m)Tc is useful complex for renal imaging and can be successfully applied as a diagnostic tool in nuclear medicine. Clinical biodistribution and radiation dosimetry studies are planned in future.

  19. .sup.100Mo compounds as accelerator targets for production of .sup.99mTc

    SciTech Connect

    Richards, Vernal; Lapi, Suzanne

    2016-09-20

    Methods of synthesizing .sup.100Mo.sub.2C and .sup.99mTcO.sub.4.sup.- are disclosed. Methods of .sup.100Mo.sub.2C generation involve thermally carburizing .sup.100MoO.sub.3. Methods of .sup.99mTcO.sub.4 generation involve proton bombardment of .sup.100Mo.sub.2C in a cyclotron. Yields of .sup.99mTcO.sub.4 can be increased by sintering .sup.100Mo.sub.2C prior to bombardment. The methods also include recycling of .sup.100Mo.sub.2C to form .sup.100MoO.sub.3. SPECT images obtained using .sup.99mTcO.sub.4 generated by the disclosed methods are also presented.

  20. Effect of Co-Ligands on Chemical and Biological Properties of 99mTc(III) Complexes [99mTc(L)(CDO)(CDOH)2BMe] (L = Cl, F, SCN and N3; CDOH2 = Cyclohexanedione Dioxime)

    PubMed Central

    Zheng, Yumin; Ji, Shundong; Tomaselli, Elena; Ernest, Carley; Freiji, Tom; Liu, Shuang

    2015-01-01

    Introduction 99mTc-Teboroxime ([99mTcCl(CDO)(CDOH)2BMe]) is a member of the BATO (boronic acid adducts of technetium dioximes) class of 99mTc(III) complexes. This study sought to explore the impact of co-ligands on solution stability, heart uptake and myocardial retention of [99mTc(L)(CDO)(CDOH)2BMe] (99mTc-Teboroxime: L = Cl; 99mTc-Teboroxime(F): L = F; 99mTc-Teboroxime(SCN): L = SCN; and 99mTc-Teboroxime(N3): L = N3). Methods Radiotracers 99mTc-Teboroxime(L) (L = F, SCN and N3) were prepared by reacting 99mTc-Teboroxime with NaF, NaSCN and NaN3, respectively. Biodistribution and imaging studies were carried out in Sprague-Dawley rats. Image quantification was performed to compare their heart retention and liver clearance kinetics. Results Complexes 99mTc-Teboroxime(L) (L = F, SCN and N3) were prepared in high yield with high radiochemical purity. All new radiotracers were stable for >6 h in the kit matrix. In its HPLC chromatogram, 99mTc-Teboroxime showed one peak at ~15.5 min, which was shorter than that of 99mTc-Teboroxime(F) (~16.4 min). There were two peaks for 99mTc-Teboroxime(SCN) at 16.5 and 18.3 min. 99mTc-Teboroxime(N3) appeared as a single peak at 18.4 min. Their heart retention and liver clearance curves were best fitted to the bi-exponential decay function. The half-times of fast/slow components were 1.6 ± 0.4/60.7±8.9 min for 99mTc-Teboroxime, 0.8±0.2/101.7±20.7 min for 99mTc-Teboroxime(F), 1.2±0.3/84.8±16.6 min for 99mTc-Teboroxime(SCN), and 2.9±0.9/51.6±5.0 min for 99mTc-Teboroxime(N3). The 2-min heart uptake followed the order of 99mTc-Teboroxime (3.00±0.37%ID/g) > 99mTc-Teboroxime(N3) (2.66±0.01 %ID/g) ≈ 99mTc-Sestamibi (2.55±0.46 %ID/g) > 99mTcN-MPO (2.38±0.15 %ID/g). 99mTc-Teboroxime remains the best in first-pass extraction. The best image acquisition window is 0 – 5 min for 99mTc-Teboroximine and 0 – 15 min for 99mTc-Teboroximine(N3). Conclusion Co-ligands had significant impact on the heart uptake and myocardial retention

  1. Evaluation of (99m)Tc(i)-tricarbonyl complexes of fluoroquinolones for targeting bacterial infection.

    PubMed

    Nayak, Dipak Kumar; Baishya, Rinku; Halder, Kamal Krishna; Sen, Tuhinadri; Sarkar, Bharat R; Ganguly, Shantanu; Das, M K; Debnath, Mita Chatterjee

    2012-11-01

    The aim of this study was to develop (99m)Tc(CO)(3)-labeled fluoroquinolones as novel SPECT radiopharmaceuticals for imaging bacterial infection. Fluoroquinolones, e.g., ofloxacin (OFX), levofloxacin (LVX), lomefloxacin (LMX) and norfloxacin (NFX) were labeled with a fac-[(99m)Tc(CO)(3)(H(2)O)(3)](+) precursor. The radiochemical purity of the radiopharmaceuticals exceeded 97% as determined by thin layer chromatography and HPLC. No further purification was necessary before injection. The Re(CO)(3) complex of one of the fluoroquinolones (levofloxacin) was synthesized using [Re(CO)(3)(H(2)O)(3)]OTf and Re(CO)(5)Br precursors in separate experiments and characterized by IR, NMR and mass spectroscopic analysis. These studies revealed the formation of a single species in which the piperazinyl nitrogen and the -COOH group attached to the benzoxazine ring system of quinolone were involved in co-ordination to the Re(CO)(3) core. The HPLC elution pattern and retention time of the Re(CO)(3)-LVX complex were comparable to those of the corresponding (99m)Tc(CO)(3)-complex proving their similarity. When incubated in isotonic saline and serum up to 24 h (99m)Tc(CO)(3)-labeled fluoroquinolones exhibited good in vitro stability. Biodistribution studies performed at different time points on rats intramuscularly infected with S. aureus as well as on rats with sterile inflammation revealed a higher uptake in the infected area than the turpentine induced inflamed area. The uptake in infected thigh was significant with (99m)Tc(CO)(3)-OFX followed by (99m)Tc(CO)(3)-LVX. The mean ratios of the uptake in infected/non-infected thighs were 4.75 and 4.27 at 8 h and 24 h, respectively, for (99m)Tc(CO)(3)-OFX and 4.42 and 4.18 at 24 h and 8 h, respectively, for (99m)Tc(CO)(3)-LVX. The above abscess to muscle ratios were higher than reported for (99m)Tc-ciprofloxacin and other (99m)Tc-labeled fluoroquinolones. Scintigraphy studies also showed a significant uptake in the infectious lesions

  2. Structural, electronic, superconducting and mechanical properties of ReC and TcC

    SciTech Connect

    Kavitha, M.; Priyanga, G. Sudha; Rajeswarapalanichamy, R. Santhosh, M.

    2015-06-24

    The structural, electronic, superconducting and mechanical properties of ReC and TcC are investigated using density functional theory calculations. The lattice constants, bulk modulus, and the density of states are obtained. The calculated lattice parameters are in good agreement with the available results. The density of states reveals that ReC and TcC exhibit metallic behavior at ambient condition. A pressure-induced structural phase transition is observed in both materials.

  3. Three-Component Spectroelectrochemical Sensor Module for the Detection of Pertechnetate (TcO4-)

    SciTech Connect

    Chatterjee, Sayandev; Bryan, Samuel A.; Seliskar, Carl J.; Heineman, William R.

    2013-07-01

    This review looks at the advancements in the development of a sensor for technetium (Tc) that is applicable to characterizing and monitoring the vadose zone and associated subsurface water. Subsurface contamination by Tc is of particular concern for two reasons: the extremely long lifetime of its most common isotope 99Tc (half-life = 2 x 105 years) and the fast migration in soils of pertechnetate (TcO4–) which is considered to be the dominant 99Tc species in ground water. TcO4– does not have a characteristic spectral signature which prevents its rapid, sensitive, and economic in-situ detection. To address this problem, a novel spectroelectrochemical sensor has been designed that combines three modes of selectivity (electrochemistry, spectroscopy, and selective partitioning) into a single sensor to substantially improve specificity which is critical in the specific detection of an analyte in the presence of potential interfering species. The sensor consists of a basic spectroelectrochemical configuration: a waveguide with an optically transparent electrode (OTE) that is coated with a thin chemically-selective film that preconcnetrates the analyte. The key to adapting this generic sensor to detect TcO4– and Tc complexes lies in the development of chemically-selective films that preconcentrate the analyte and, when necessary, chemically convert it into a complex with electrochemical and spectroscopic properties appropriate for sensing. This review focuses on the general concept of the sensor and the rationale for the selection of the specific components of choice, the development and characterization of the sensor for the different detection modules, the synthesis and characterization of complexes relevant in the detection of technetium, and the progress in the utilization of the sensor module for the effective detection of these complexes.

  4. Technetium-99 ((99)Tc) in annual growth segments of knotted wrack (Ascophyllum nodosum).

    PubMed

    Heldal, Hilde Elise; Sjøtun, Kjersti

    2010-10-15

    The distribution of technetium-99 ((99)Tc) in annual growth segments of the brown seaweed Ascophyllum nodosum (Fucales, Phaeophyceae) from the southwestern coast of Norway is examined in samples collected from January to November 2006. A twenty-fold increase in the (99)Tc-concentration from the youngest to the oldest growth segments was found. The concentrations ranged from 42 to 98Bq/kg dry weight (d.w.) and from 964 to 1000Bq/kg d.w. in growth segments formed in 2006 and 1996, respectively. In addition, a seasonal variation in the (99)Tc concentration was observed in the actively growing 2006-segments: concentrations decreased from 98Bq/kg d.w. in April to 54Bq/kg d.w. in June; there was a further reduction from June to August (42Bq/kg d.w.); and, finally there was an increase from August to November (93Bq/kg d.w.). In most of the segments formed between 2000 and 2005, there was a tendency of slightly decreasing (99)Tc-concentrations between June and November but this pattern was not observed for the older growth segments. In order to find an explanation for the non-homogenous distribution of (99)Tc within thalli of A. nodosum, different hypotheses are discussed. Uptake and elimination of (99)Tc appears to be most pronounced in the actively growing segments. To date, such non-homogenous distribution of (99)Tc within thalli of A. nodosum has not been taken into consideration, neither in connection with sample collection nor analysis. This paper shows that special protocols must be followed if A. nodosum is going to be used as a bioindicator for (99)Tc in the marine environment. A sampling strategy is proposed.

  5. 99mTc-Tetrofosmin Uptake Correlates with the Sensitivity of Glioblastoma Cell Lines to Temozolomide

    PubMed Central

    Alexiou, George A.; Xourgia, Xanthi; Gerogianni, Paraskevi; Vartholomatos, Evrysthenis; Kalef-Ezra, John A.; Fotopoulos, Andreas D.; Kyritsis, Athanasios P.

    2017-01-01

    99mTc-tetrofosmin (99mTc-TF) is a single-photon emission computed tomography tracer that has been used for brain tumor imaging. The aim of the study was to assess if 99mTc-TF uptake by glioblastoma cells correlates with their response to temozolomide (TMZ). We investigated the correlation of TMZ antitumor effect with the 99mTc-TF uptake in two glioblastoma cell lines. The U251MG cell line is sensitive to TMZ, whereas T98G is resistant. Viability and proliferation of the cells were examined by trypan blue exclusion assay and xCELLigence system. Cell cycle was analyzed with flow cytometry. The radioactivity in the cellular lysate was measured with a gamma scintillation counter. TMZ induced G2/M cell cycle arrest in U251MG cells, whereas there was no effect on cell cycle in T98G cells. Lower 99mTc-TF uptake was observed in U251MG cells that were exposed to TMZ compared to control (P = 0.0159). No significant difference in respect to 99mTc-TF uptake was found in T98G cells when exposed to TMZ compared to control (P = 0.8). With 99mTc-TF, it was possible to distinguish between TMZ-sensitive and resistant glioblastoma cells within 6 h of treatment initiation. Thus, 99mTc-TF uptake may consist a novel approach to assess an early response of glioblastoma to chemotherapy and deserves further investigation. PMID:28217019

  6. Leaching Tc-99 from SRP glass in simulated tuff and salt groundwaters

    SciTech Connect

    Bibler, N E; Jurgensen, A R

    1987-01-01

    Results of leach tests with Tc-99 doped SRP borosilicate waste glass are presented. The glass was prepared by melting a mixture of SRP 165 powdered frit doped with a carrier free solution of Tc-99 at 1150{sup 0}C. Dissolution of portions of the resulting glass indicated that the Tc-99 was distributed homogeneously throughout the glass. Static leach tests up to 90 days were performed at 90{sup 0}C in J-13 tuff groundwater or WIPP brine A at a SA/V of 100m{sup -1}. Normalized mass losses were calculated for Tc-99 as well as all the major elements in the glass. Results indicated that under ambient oxidizing conditions Tc-99 leached no faster than the glass-forming elements of the glass. In J-13 water, Tc-99 leached congruently with B. In WIPP brine A, it leached congruently with Si. Leach rates for Li were higher in both groundwaters, probably due to a contribution from an ion exchange mechanism. Leach tests were performed under reducing conditions in J-13 water by adding Zn/Hg amalgam to the leachate. In these tests the pH increased significantly, probably because of the reaction of the amalgam with the water. In a 21-day test, the pH increased to 13 and leach rates for the glass were very high. Even though there was signifcant dissolution of the glass, the normalized mass loss based on Tc-99 was only 0.02g/m{sup 2}. This result and the fact that reducing conditions at normal pH values do not significantly affect the dissolution of the glass, indicate that the low concentrations for Tc-99 obtained under reducing conditions are due to is solubility and not due to an increased durability of the glass. 14 refs., 2 figs., 5 tabs.

  7. Pushing TC to 27.5 K in a heavy atom radical ferromagnet.

    PubMed

    Lekin, Kristina; Ogata, Kazuma; Maclean, Adrian; Mailman, Aaron; Winter, Stephen M; Assoud, Abdeljalil; Mito, Masaki; Tse, John S; Desgreniers, Serge; Hirao, Naohisa; Dube, Paul A; Oakley, Richard T

    2016-11-24

    In the solid state the iodo-substituted bisdiselenazolyl radical 1c orders as a ferromagnet with TC = 10.5 K. With the application of pressure TC rises rapidly, reaching a value of 27.5 K at 2.4 GPa. The accompanying structural and magnetic changes have been examined by high resolution powder X-ray diffraction and by DFT calculations of magnetic exchange interactions.

  8. Detection of gastritis by /sup 99m/Tc-labeled red-blood-cell scintigraphy

    SciTech Connect

    Wilton, G.P.; Wahl, R.L.; Juni, J.E.; Froelich, J.W.

    1984-10-01

    Gastritis is a common condition, with a variety of causes, that is diagnosed most often by barium upper gastrointestinal tract series or endoscopy. The authors report a case in which gastritis without active bleeding was apparent in scintiscans obtained during the evaluation of GI bleeding using /sup 99m/Tc-labeled red blood cells (TcRBC). The scintigraphic findings that suggest gastritis are described.

  9. Enhancing Tc in field-doped fullerenes by applying uniaxial stress

    NASA Astrophysics Data System (ADS)

    Koch, Erik

    2002-08-01

    Capitalizing on the two-dimensional nature of superconductivity in field-effect doped C60, we show that it should be possible to increase the transition temperature Tc by applying uniaxial stress perpendicular to the gate electrode. This method not only holds the promise of substantially enhancing Tc (by about 30 K per GPa), but also provides a sensitive check of the current understanding of superconductivity in the doped fullerenes.

  10. Water-stable fac-{TcO₃}⁺ complexes - a new field of technetium chemistry.

    PubMed

    Braband, Henrik

    2011-01-01

    The development of technetium chemistry has been lagging behind that of its heavier congener rhenium, primarily because the inherent radioactivity of all Tc isotopes has limited the number of laboratories that can study the chemistry of this fascinating element. Although technetium is an artificial element, it is not rare. Significant amounts of the isotope (99)Tc are produced every day as a fission byproduct in nuclear power plants. Therefore, a fundamental understanding of the chemistry of (99)Tc is essential to avoid its release into the environment. In this article the chemistry of technetium at its highest oxidation state (+VII) is reviewed with a special focus on recent developments which make water-stable complexes of the general type [TcO(3)(tacn-R)](+) (tacn-R = 1,4,7-triazacyclononane or derivatives) accessible. Complexes containing the fac-{TcO(3)}(+) core display a unique reactivity. In analogy to [OsO(4)] and [RuO(4)], complexes containing the fac-{TcO(3)}(+) core undergo with alkenes metal-mediated, vicinal cis-dihydroxylation reactions (alkene-glycol interconversion) in water via a (3+2)-cycloaddition reaction. Therefore, water-stable fac-{(99m)TcO(3)}(+) complexes pave the way for a new labeling strategy for radiopharmaceutical applications, based on (3+2)-cycloaddition reactions. This new concept for the labeling of biomolecules with small [(99m)TcO(3)(tacn-R)](+)-type complexes by way of a (3+2)-cycloaddition with alkenes is discussed in detail. The herein reported developments in high-valent technetium chemistry create a new field of research with this artificial element. This demonstrates the potential of fundamental research to provide new impetus of innovation for the development of new methods for radiopharmaceutical applications.

  11. Intense splenic 99mTc-MDP uptake in a patient with myelofibrosis.

    PubMed

    Chen, Ming; Liu, Chun; Yang, Jigang

    2013-12-01

    99mTc-MDP bone scan was performed in a 49-year-old woman with breast cancer. Whole-body bone scan showed multiple foci of increased MDP activity in the bone and intense splenic 99mTc-MDP uptake. Initial bone marrow aspiration in multiple locations yielded no blood cells. A subsequent bone marrow biopsy in the left anterior superior iliac spine showed myelofibrosis in addition to the known bone metastasis.

  12. [Imaging of hyperparathyroidism-Ultrasonography and 99mTc-MIBI scintigraphy-].

    PubMed

    Kawabe, Joji; Higashiyama, Shigeaki; Yoshida, Atsushi; Kotani, Kohei; Shiomi, Susumu

    2016-06-01

    Treatments for primary hyperparathyroidism due to adenoma, hyperplasia and carcinoma and secondary hyperparathyroidism are mainly surgical resections of them. Accurate imaging diagnoses of the existences and the regions are very important for reductions of invasiveness. We describe ultrasonography and (99m)Tc-MIBI scintigraphy of hyperparathyroidism. We explain an advantage, a disadvantage and diagnosability of these modalities. We mention utilities of SPECT/CT, too. We show echogram and (99m)Tc-MIBI scintigraphy images about 3 cases of hyperparathyroidism.

  13. Impact of Bidentate Chelators on Lipophilicity, Stability and Biodistribution Characteristics of Cationic 99mTc-Nitrido Complexes

    PubMed Central

    Liu, Shuang; He, Zhengjie; Hsieh, Wen-Yuan; Kim, Yong-Seung

    2008-01-01

    This report describes synthesis and evaluation of novel cationic 99mTc-nitrido complexes, [99mTcN(L)(PNP)]+ (L = ma, ema, tma, etma and mpo; PNP = PNP5, PNP6 and L6), as potential radiotracers for heart imaging. Cationic complexes [99mTcN(L)(PNP)]+ were prepared in two steps. For example, reaction of succinic dihydrazide with 99mTcO4− in the presence of excess stannous chloride and PDTA resulted in the [99mTcN(PDTA)n] intermediate, which then reacted Hmpo and PNP6 at 100 °C for 10 – 15 min to give [99mTcN(mpo)(PNP6)]+ in >90% yield. It was found that bidentate chelators have a significant impact on lipophilicity, solution stability, biodistribution and metabolic stability of cationic 99mTc-nitrido complexes. The fact that [99mTcN(ema)(PNP6)]+ decomposes rapidly in presence of cysteine (1 mg/mL) while [99mTcN(etma)(PNP6)]+ and [99mTcN(mpo)(PNP6)]+ remain stable for >6 h under the same conditions strongly suggests that thione-S donors in bidentate chelators increase the solution stability of their cationic 99mTc-nitrido complexes. Biodistribution studies were performed on four cationic 99mTc-nitrido complexes in Sprague-Dawley rats. [99mTcN(etma)(PNP5)]+ is of particular interest due to its high initial heart uptake (1.81±0.35 %ID/g at 5 min postinjection), and long myocardial retention (1.99±0.47 %ID/g at 120 min postinjection). The heart/liver ratio of [99mTcN(etma)(PNP5)]+ (6.06±1.48) at 30 min postinjection is almost identical that of 99mTcN-DBODC5 (6.01±1.45), and is >2 times better than that of 99mTc-sestamibi (2.90±0.22). Results from metabolism studies show that [99mTcN(etma)(PNP5)]+ has no significant metabolism in the urine; but it does show significant metabolism in feces samples at 120 min postinjection. Planar imaging studies suggest that [99mTcN(etma)(PNP5)]+ might be able to give clinically useful images of the heart as early as 30 min postinjection. [99mTcN(etma)(PNP5)]+ is a very promising candidate for more pre-clinical evaluations in

  14. [99mTc-ECD dynamic SPECT in "luxury perfusion" of subacute stroke].

    PubMed

    Ogasawara, K; Fujiwara, S; Yoshimoto, T

    1995-11-01

    To evaluate the cerebral pharmacokinetics of 99mTc-ethyl cysteinate dimer (99mTc-ECD) at blood flow levels beyond the normal range, we investigated "luxury perfusion" in subacute stroke, ictal hyperperfusion in epilepsy and post-decompressive hyperemia in head trauma. All 7 patients showed a hyperactive area on SPECT studies using 99mTc-HM-PAO. 99mTc-ECD static image demonstrated a hyperactive area in both epilepsy and head trauma, and a hypoactive area in "luxury perfusion." On the dynamic SPECT of 99mTc-ECD in both epilepsy and head trauma, brain distribution of the tracer was determined within 2 min. postinjection and remained stable for up to 1 hour; however, "luxury perfusion" area showed a change from initial hyperactivity to late hypoactivity with the passage of time. The time activity curve in "luxury perfusion" area demonstrated a steep decrease of counts/pixel for up to 4-5 minutes postinjection, and a moderate decrease in the following phase. The early wash-out mechanism of 99mTc-ECD from "luxury perfusion" area can be described by a biexponential function including an initial steep decrease representing the rapid loss of the lipophilic complexes which were not metabolized in injured brain tissue.

  15. Molybdenum target specifications for cyclotron production of 99mTc based on patient dose estimates

    NASA Astrophysics Data System (ADS)

    Hou, X.; Tanguay, J.; Buckley, K.; Schaffer, P.; Bénard, F.; Ruth, T. J.; Celler, A.

    2016-01-01

    In response to the recognized fragility of reactor-produced 99Mo supply, direct production of 99mTc via 100Mo(p,2n)99mTc reaction using medical cyclotrons has been investigated. However, due to the existence of other Molybdenum (Mo) isotopes in the target, in parallel with 99mTc, other technetium (Tc) radioactive isotopes (impurities) will be produced. They will be incorporated into the labeled radiopharmaceuticals and result in increased patient dose. The isotopic composition of the target and beam energy are main factors that determine production of impurities, thus also dose increases. Therefore, they both must be considered when selecting targets for clinical 99mTc production. Although for any given Mo target, the patient dose can be predicted based on complicated calculations of production yields for each Tc radioisotope, it would be very difficult to reverse these calculations to specify target composition based on dosimetry considerations. In this article, a relationship between patient dosimetry and Mo target composition is studied. A simple and easy algorithm for dose estimation, based solely on the knowledge of target composition and beam energy, is described. Using this algorithm, the patient dose increase due to every Mo isotope that could be present in the target is estimated. Most importantly, a technique to determine Mo target composition thresholds that would meet any given dosimetry requirement is proposed.

  16. Investigation of Tc Migration Mechanism During Bulk Vitrification Process Using Re Surrogate

    SciTech Connect

    Kim, Dong-Sang; Bagaasen, Larry M.; Crum, Jarrod V.; Fluegel, Alex; Gallegos, Autumn B.; Martinez, Baudelio; Matyas, Josef; Meyer, Perry A.; Paulsen, Dan; Riley, Brian J.; Schweiger, Michael J.; Stewart, Charles W.; Swoboda, Robert G.; Yeager, John D.

    2006-12-04

    As a part of Bulk vitrification (BV) performance enhancement tasks, Laboratory scoping tests were performed in FY 2004-2005 to explore possible ways to reduce the amount of soluble Tc in the BV waste package. Theses scoping tests helped identify which mechanisms play an important role in the migration of Tc in the BV process (Hrma et al. 2005 and Kim et al. 2005). Based on the results from these scoping tests, additional tests were identified that will improve the understanding of Tc migration and to clearly identify the dominant mechanisms. The additional activities identified from previous studies were evaluated and prioritized for planning for Tasks 29 and 30 conducted in FY2006. Task 29 focused on the improved understanding of Tc migration mechanisms, and Task 30 focused on identifying the potential process changes that might reduce Tc/Re migration into the castable refractory block (CRB). This report summarizes the results from the laboratory- and crucible-scale tests in the lab for improved Tc migration mechanism understanding utilizing Re as a surrogate performed in Task 29.

  17. Almahata Sitta (=asteroid 2008 TC3) and the search for the ureilite parent body

    NASA Astrophysics Data System (ADS)

    Jenniskens, Peter; Vaubaillon, Jérémie; Binzel, Richard P.; DeMeo, Francesca E.; Nesvorný, David; Bottke, William F.; Fitzsimmons, Alan; Hiroi, Takahiro; Marchis, Franck; Bishop, Janice L.; Vernazza, Pierre; Zolensky, Michael E.; Herrin, Jason S.; Welten, Kees C.; Meier, Matthias M. M.; Shaddad, Muawia H.

    2010-10-01

    This article explores what the recovery of 2008 TC3 in the form of the Almahata Sitta meteorites may tell us about the source region of ureilites in the main asteroid belt. An investigation is made into what is known about asteroids with roughly the same spectroscopic signature as 2008 TC3. A population of low-inclination near-Earth asteroids is identified with spectra similar to 2008 TC3. Five asteroid families in the Main Belt, as well as a population of ungrouped asteroids scattered in the inner and central belts, are identified as possible source regions for this near-Earth population and 2008 TC3. Three of the families are ruled out on dynamical and spectroscopic grounds. New near-infrared spectra of 142 Polana and 1726 Hoffmeister, lead objects in the two other families, also show a poor match to Almahata Sitta. Thus, there are no Main Belt spectral analogs to Almahata Sitta currently known. Space weathering effects on ureilitic materials have not been investigated, so that it is unclear how the spectrum of the Main Belt progenitor may look different from the spectra of 2008 TC3 and the Almahata Sitta meteorites. Dynamical arguments are discussed, as well as ureilite petrogenesis and parent body evolution models, but these considerations do not conclusively point to a source region either, other than that 2008 TC3 probably originated in the inner asteroid belt.

  18. The function of Sn(II)-apatite as a Tc immobilizing agent

    NASA Astrophysics Data System (ADS)

    Asmussen, R. Matthew; Neeway, James J.; Lawter, Amanda R.; Levitskaia, Tatiana G.; Lukens, Wayne W.; Qafoku, Nikolla P.

    2016-11-01

    At the U.S. Department of Energy Hanford Site, Tc-99 is a component of low-activity waste (LAW) fractions of the nuclear tank waste and removal of Tc from LAW streams would greatly benefit the site remediation process. In this study, we investigated the removal of Tc(VII), as pertechnetate, from deionized water (DIW) and a LAW simulant through batch sorption testing and solid phase characterization using tin (II) apatite (Sn-A) and SnCl2. Sn-A showed higher levels of Tc removal from both DIW and LAW simulant. Scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/XEDS) and X-ray absorption spectroscopy (XAS) of reacted Sn-A in DIW showed that TcO4- is reduced to Tc(IV) on the Sn-A surface. The performance of Sn-A in the LAW simulant was lowered due to a combined effect of the high alkalinity, which lead to an increased dissolution of Sn from the Sn-A, and a preference for the reduction of Cr(VI).

  19. Secrets of Soil Survival Revealed by the Genome Sequence of Arthrobacter aurescens TC1

    PubMed Central

    Daugherty, Sean C; DeBoy, Robert T; Emerson, Joanne B; Shvartzbeyn, Alla; Radune, Diana; Vamathevan, Jessica; Riggs, Florenta; Grinberg, Viktoria; Khouri, Hoda; Wackett, Lawrence P; Nelson, Karen E; Sadowsky, Michael J

    2006-01-01

    Arthrobacter sp. strains are among the most frequently isolated, indigenous, aerobic bacterial genera found in soils. Member of the genus are metabolically and ecologically diverse and have the ability to survive in environmentally harsh conditions for extended periods of time. The genome of Arthrobacter aurescens strain TC1, which was originally isolated from soil at an atrazine spill site, is composed of a single 4,597,686 basepair (bp) circular chromosome and two circular plasmids, pTC1 and pTC2, which are 408,237 bp and 300,725 bp, respectively. Over 66% of the 4,702 open reading frames (ORFs) present in the TC1 genome could be assigned a putative function, and 13.2% (623 genes) appear to be unique to this bacterium, suggesting niche specialization. The genome of TC1 is most similar to that of Tropheryma, Leifsonia, Streptomyces, and Corynebacterium glutamicum, and analyses suggest that A. aurescens TC1 has expanded its metabolic abilities by relying on the duplication of catabolic genes and by funneling metabolic intermediates generated by plasmid-borne genes to chromosomally encoded pathways. The data presented here suggest that Arthrobacter's environmental prevalence may be due to its ability to survive under stressful conditions induced by starvation, ionizing radiation, oxygen radicals, and toxic chemicals. PMID:17194220

  20. The Role of the Trypanosoma cruzi TcNRBD1 Protein in Translation

    PubMed Central

    Oliveira, Camila; Carvalho, Paulo Costa; Goldenberg, Samuel

    2016-01-01

    The regulation of gene expression in trypanosomatids occurs mainly at the post-transcriptional level. Despite the importance of this type of control in Trypanosoma cruzi, few RNA binding proteins have been characterized. The RRM domain (RNA Recognition Motif) is one of the most abundant domains found in RNA-binding proteins in higher eukaryotes. Proteins containing the RRM domain are involved in the majority of post-transcriptional processes regulating gene expression. In this work, we aimed to characterize the protein TcNRBD1 from T. cruzi. TcNRBD1 is an RNA-binding protein that contains 2 RRM domains and is the ortholog of the P34 and P37 proteins from Trypanosoma brucei. The TcNRBD1 protein is expressed in all developmental stages of T. cruzi, and its localization pattern is concentrated at the perinuclear region. TcNRBD1 is associated with polysomes and with the 80S monosomes. Furthermore, sequencing of the mRNAs bound to TcNRBD1 allowed the identification of several transcripts that encode ribosomal proteins. Immunoprecipitation assays followed by mass spectrometry showed that the protein complexes with several ribosomal proteins from both the 40S and 60S subunits. In summary, the results indicate that TcNRBD1 is associated with different parts of the translation process, either by regulating mRNAs that encode ribosomal proteins or by acting in some step of ribosome assembly in T. cruzi. PMID:27760165

  1. Characterization of TcHMGB, a high mobility group B family member protein from Trypanosoma cruzi.

    PubMed

    Cribb, Pamela; Perozzi, Marina; Villanova, Gabriela Vanina; Trochine, Andrea; Serra, Esteban

    2011-09-01

    High mobility group B (HMGB) proteins are highly abundant non-histone chromatin proteins that play important roles in the execution and control of many nuclear functions. Based on homology searches, we identified the coding sequence for the TcHMGB protein, an HMGB family member from Trypanosoma cruzi. TcHMGB has two HMG box domains, similar to mammalian HMGBs, but lacks the typical C-terminal acidic tail. Instead, it contains a 110 amino acid long N-terminal domain. The TcHMGB N-terminal domain is conserved between the TriTryp sequences (70-80% similarity) and seems to be characteristic of kinetoplastid HMGBs. Despite these differences, TcHMGB maintains HMG box architectural functions: we demonstrated that the trypanosomatid HMGB binds distorted DNA structures such as cruciform DNA in gel shift assays. TcHMGB is also able to bend linear DNA as determined by T4 ligase circularization assays, similar to other HMGB family members. Immunofluorescence and western blot assays showed that TcHMGB is a nuclear protein expressed in all life cycle stages. Protein levels, however, seem to vary throughout the life cycle, which may be related to previously described changes in heterochromatin distribution and transcription rates.

  2. Discrepant 99mTc-ECD images of CBF in patients with subacute cerebral infarction: a comparison of CBF, CMRO2 and 99mTc-HMPAO imaging.

    PubMed

    Shishido, F; Uemura, K; Inugami, A; Ogawa, T; Fujita, H; Shimosegawa, E; Nagata, K

    1995-08-01

    Three patients with subacute ischemic cerebral infarction examined by SPECT with 99mTc-ECD and PET within the same day showed signs of luxury perfusion in the subacute phase, which is between 9 to 20 days after the onset. A 99mTc-HMPAO SPECT study was also performed within 2 days of the ECD-SPECT study. ECD-SPECT images of three patients displayed a focal decreased uptake in the infarcted lesions, while in infarcted foci, there was almost equivalent or increased CBF compared to normal and unaffected areas, decreased CMRO2, and high HMPAO uptake. The ECD-SPECT results were similar to those of CMRO2 rather than CBF, though the HMPAO-SPECT image was similar to that of CBF. In one patient, HMPAO images revealed hyperfixation of the tracer. In the chronic phase and in the acute phase before 5 days after the onset, there were no discrepancies among the ECD-SPECT, CBF, HMPAO-SPECT, and CMRO2 images. These observations indicated that 99mTc-ECD is a good indicator of damaged brain tissues in subacute ischemic infarction. They also suggested that 99mTc-ECD is a potential agent with which to evaluate cerebral tissue viability in some pathological states of cerebrovascular disease. The characteristics may be suitable for confirming the effects of thrombolytic therapy in acute ischemia, because these conditions often show signs of luxury perfusion when the therapy is successful.

  3. Activity measurements of the radionuclide 99mTc for the IFIN-HH, Romania in the ongoing comparison BIPM.RI(II)-K4.Tc-99m

    NASA Astrophysics Data System (ADS)

    Michotte, C.; Sahagia, M.; Ioan, M. R.; Antohe, A.; Luca, A.

    2014-01-01

    In 2013, a comparison of activity measurements of 99mTc using the Transfer Instrument of the International Reference System (SIRTI) took place at the Institutul National de Cercetare - Dezvoltare in Fizica si Inginerie Nucleara - 'Horia Hulubei' (IFIN-HH, Romania). Ampoules containing about 21 kBq and 40 kBq of a 99mTc solution were measured in the SIRTI for, respectively, one and three half-lives. The comparison, identifier BIPM.RI(II)-K4.Tc-99m, is linked to the BIPM.RI(II)-K1.Tc-99m comparison and the degrees of equivalence with the key comparison reference value and between the present IFIN-HH result, the other K4 participants and the six participants in the K1 comparison have been evaluated. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  4. Activity measurements of the radionuclide 99mTc for the NIM, China in the ongoing comparison BIPM.RI(II)-K4.Tc-99m

    NASA Astrophysics Data System (ADS)

    Michotte, C.; Nonis, M.; Liang, J. C.; Chen, J.; Liu, H. R.; Zhang, M.; Zhao, Q.; Yang, Y. D.

    2013-01-01

    In 2012, the fourth comparison of activity measurements of 99mTc using the Transfer Instrument of the International Reference System (SIRTI) took place at the Chinese National Institute of Metrology (NIM). An ampoule containing about 70 kBq of 99mTc traceable to the NIM primary standard was measured in the SIRTI for more than three half-lives. The comparison, identifier BIPM.RI(II)-K4.Tc-99m, is linked to the BIPM.RI(II)-K1.Tc-99m comparison and the degrees of equivalence with the key comparison reference value and between the present NIM result, the other K4 participant and the six participants in the K1 comparison have been evaluated. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  5. The trajectory and impact circumstances of asteroid 2008 TC3

    NASA Astrophysics Data System (ADS)

    Chodas, Paul; Chesley, S.; Yeomans, D.

    2010-05-01

    On October 6, 2008, the small newly discovered near-Earth asteroid 2008 TC3 was found to be on an Earth-impacting trajectory, with impact less than 20 hours away. This was the first ever predicted impact of a near-Earth object. Fortunately, it was immediately clear that the object was only a few meters in size and would therefore almost certainly break up when it entered the Earth's atmosphere. We review the pre-impact orbit computations and predictions, the post-impact reconstructions of the trajectory, and the trajectory geometry. The first prediction of impact was made by the Minor Planet Center (MPC), which quickly made the discovery and subsequent follow-up observations available to the astronomical community and contacted us at the NASA/JPL Near-Earth Object Program Office. Our impact predictions indicated that the atmospheric entry would occur over northern Sudan around 02:46 UT on October 7. Over the course of the day, the number of observations sky-rocketed to several hundred, and the impact prediction uncertainty shrank to ±3 km. Topocentric parallax up to 15 degrees is present in the data and the rates of motion approached 13.4 arcsec/s prior to the object's disappearance into the Earth's umbra. Detections of the actual atmospheric impact event suggested that it was an airburst explosion at an altitude of 37 km with an energy equivalent of about one kiloton of TNT. The airburst occurred at 02:45:45 UT at about 32.2 East longitude and 20.8 North latitude, matching the final impact predictions to within 0.2 s in time and 1.5 km in position. We compute Monte Carlo clones of the final orbit to investigate possible source orbits. Trajectory dispersions remain fairly compact as far back as 1961 , when an Earth close approach at 0.18 ± 0.12 AU scatters the predictions. Only statistical characterizations of the earlier trajectory are possible.

  6. ISO TC211 standards on Provenance for Earth science

    NASA Astrophysics Data System (ADS)

    Di, L.; Deng, M.

    2014-12-01

    Data provenance, also called lineage, records the derivation history of a data product. The history could include the algorithms used, the process steps taken, the computing environment run, data sources input to the processes, the organization/person responsible for the product, etc. Provenance provides important information to data users for them to determine the usability and reliability of the product. In the science domain, the data provenance is especially important since scientists need to use the information to determine the scientific validity of a data product and to decide if such a product can be used as the basis for further scientific analysis. Provenance is a kind of metadata. In Earth science domain, the International Organization for Standardization (ISO) Technical Committee 211 (ISO TC 211) have set geospatial metadata standards for geospatial data, including ISO 19115:2003-Metadata, ISO 19115-2:2009-Metadata-Part 2: Extensions for imagery and gridded data, and ISO 19115-1:2014 - Metadata -- Part 1: Fundamentals. ISO 19115 and ISO 19115-1 define the fundamental metadata for documenting geospatial data products, and ISO 19115-2 provides additional metadata classes for imagery and gridded data. ISO 19115-1:2014 is the revised version of ISO 19115:2003. ISO 19115 and ISO 19115-1 define fundamental lineage information classes and subclasses. They miss some key information classes needed for documenting the provenance in the Web service environment, such as the running environment, the algorithms, and software executables. However, ISO 19115-2 extends the lineage model in ISO 19115 and provides additional metadata classes needed for documenting provenance information. The combination of lineage models in ISO 19115 and ISO 19115-2 provides a comprehensive provenance information model needed for the web service environment. Currently the ISO Provence standard is not compatible with W3C Prov standard. The revision of ISO 19115-2 will be started in

  7. Solubility Control of Technetium Release from Saltstone by Tc02•xH20

    SciTech Connect

    Cantrell, Kirk J.; Williams, Benjamin D.

    2013-11-12

    Saltstone leaching experiments were conducted using a modified single-pass flow-through method under anoxic conditions. The analytical results of leachates collected from these experiments were evaluated using thermodynamic modeling to determine if the data were consistent with potential solubility controlling phases. The results demonstrate that technetium concentrations in water in contact with Saltstone under anoxic conditions is controlled by the solubility of TcO2•xH2O (likely TcO2•1.6H2O). In our system equilibrium solubility appears to have been reached within two weeks at a concentration of approximately 1.5 x 10-6 M. This concentration is likely to vary as the composition of Saltstone pore fluid evolves over time. As the pH goes from the initial high values (~12.5-13) to lower values, the solubility of technetium will decrease significantly. The thermodynamic data used to determine the solubility of TcO2•1.6H2O were taken from the tabulation of critically selected thermodynamic data determined by the Nuclear Energy Agency. Solid phase characterization to demonstrate the presence of TcO2•xH2O was not possible due to the low concentrations of technetium in our samples. Previous solid phase characterization studies with cementitious waste forms that were very similar to our Saltstone samples as well as reaction products derived from reductive immobilization of TcO4- by amorphous FeS clearly indicate the presence of TcO2 with varying degrees of hydration. Although, the presence of TcSx or other reduced technetium sulfide phases in our samples cannot be ruled out, release of technetium from Saltstone will be controlled by TcO2•1.6H2O because of its higher solubility. Our results clearly demonstrate that the release mechanism of technetium from Saltstone under reducing conditions is solubility controlled by TcO2•xH2O (likely TcO2•1.6H2O); however, distribution coefficients (Kds), that describe sorption and not solubility, were calculated for

  8. 99mTc(CO)3-labeled pamidronate and alendronate for bone imaging.

    PubMed

    Palma, Elisa; Correia, João D G; Oliveira, Bruno L; Gano, Lurdes; Santos, Isabel C; Santos, Isabel

    2011-03-28

    Bone scintigraphy with (99m)Technetium-methylenediphosphonate ((99m)Tc-MDP) or (99m)Technetium-hydroxymethylenediphosphonate ((99m)Tc-HMDP) presents several limitations, namely low specificity, uncertainty in the radiopharmaceutical's molecular structure and long acquisition time after injection. Aiming to find bone-seeking radiotracers based on the core fac-[(99m)Tc(CO)(3)](+) with improved chemical and biological properties, we synthesized new conjugates (pz-PAM and pz-ALN), comprising a pyrazolyl-diamine chelating unit (pz: N,N,N donor atom set) for metal stabilization and a pendant pamidronate (PAM) or alendronate (ALN) moiety for bone targeting. The reaction of the conjugates with fac-[(99m)Tc(CO)(3)](+) yielded (> 95%) the stable complexes fac-[(99m)Tc(CO)(3)(pz-PAM)](-) (2a) and fac-[(99m)Tc(CO)(3)(pz-ALN)](-) (3a), which have been characterized by comparing their HPLC gamma-traces with the UV-vis traces of the Re surrogates 2 and 3, respectively. 2a and 3a bind strongly onto hydroxyapatite. The biodistribution studies in Balb-c mice have shown that 2a and 3a presented an high bone uptake (2a 18.3 ± 0.6% I.D./g, 3a 17.3 ± 6.1% I.D./g, at 1 h post injection), similar to (99m)Tc-MDP (17.1 ± 2.4% I.D./g, at 1 h post injection), with comparable clearance from most tissues and increased total excretion (2a 66% I.D., 3a 67% I.D. and (99m)Tc-MDP 49% I.D., at 1 h post injection). The bone-to-blood (2a 86.2, 3a 74.7) and the bone-to-muscle ratios (2a 77.7, 3a 79.0) are higher than the ones found for (99m)Tc-MDP (70.9, 47.9), at 4 h post injection. Planar whole-body gamma camera images of the rats injected with the (99m)Tc(CO)(3)-labeled pamidronate (2a) and alendronate (3a) confirmed the overall adequate biological profile of the new radiotracers for bone imaging.

  9. Radiosynthesis and evaluation of a (99m)Tc-folic acid radiotracer prepared using [(99m)TcN(PNP)](2+) metal fragment.

    PubMed

    Vats, Kusum; Subramanian, Suresh; Mathur, Anupam; Sarma, Haladhar Dev; Banerjee, Sharmila

    2017-03-01

    Folate receptors (FR) are over-expressed on a wide variety of tumor cells and are a potential molecular target for radiolabeled folates. In this respect, several SPECT and PET based radiofolates have been evaluated in the past albeit with their high renal uptake posing limitation towards their clinical use. To overcome this, a new (99m)Tc labeled folic acid was synthesized via the use of [(99m)TcN(PNP)](2+) metal fragment, where the presence of the latter pharmacophore redirects in vivo clearance via the hepatobiliary pathway. In this respect, folic acid was derivatized at the γ-acid group with a cysteine BFCA (bifunctional chelating agent) and subsequently reacted with the preformed [(99m)TcN](2+) intermediate in presence of PNP2 (bisphosphine) ligand, to yield the final complex. While preliminary, in vivo distribution of the complex exhibited high association of activity with liver and intestines and provided support to the rationality of the present design as clearance of labeled folic acid could be effected via the hepatic route, the in vitro studies of the folic acid-cysteine conjugate carried out in KB-31 cells, did not show much promise with reduction in receptor affinity in comparison with the native folic acid. The route followed herein to prepare a folic-acid based radiotracer constitutes the first report of radiolabeling folic acid using the [(99m)TcN(PNP)](2+) as a radiosynthon. Modification in the structure of conjugate by linking the BFCA through a long-chain linker can be envisaged to improve the affinity of [(99m)TcN(PNP)]-folic acid complex towards FRs.

  10. Adipose tissue hyperplasia with enhanced adipocyte-derived stem cell activity in Tc1(C8orf4)-deleted mice.

    PubMed

    Jang, Hayoung; Kim, Minsung; Lee, Soyoung; Kim, Jungtae; Woo, Dong-Cheol; Kim, Kyung Won; Song, Kyuyoung; Lee, Inchul

    2016-10-24

    Adipose tissue hyperplasia with increased number of adipocytes is implicated in a protective rather than deleterious effect on obesity-associated metabolic disorder. It is poorly understood how the adipose tissue cellularity is regulated. Tc1 is a gene of vertebrates that regulates diverse downstream genes. Young Tc1-deleted mice fed on standard chow diet show expanded adipose tissue with smaller adipocytes in size compared to wild type controls, representing adipose tissue hyperplasia. Tc1(-/-) mice show enhanced glucose tolerance and reduced serum lipids. Adipocyte-derived stem cells (ADSCs) from Tc1(-/-) mice show enhanced proliferative and adipogenic capacity compared to wild type controls, suggesting that the adipose hyperplasia is regulated at the stem cell level. PPARγ and CEBPα are up-regulated robustly in Tc1(-/-) ADSCs upon induction for adipogenesis. Wisp2 and Dlk1, inhibitors of adipogenesis, are down-regulated in Tc1(-/-) ADSCs compared to controls. Tc1-transfected NIH3T3 cells show higher β-catenin reporter signals than vector transfected controls, suggesting a role of canonical Wnt signaling in the Tc1-dependent adipose regulation. Our data support that Tc1 is a novel regulator for adipose stem cells. Adipose tissue hyperplasia may be implicated in the metabolic regulation of Tc1(-/-) mice.

  11. Transposon Tc1-derived, sequence-tagged sites in Caenorhabditis elegans as markers for gene mapping

    PubMed Central

    Korswagen, Hendrik C.; Durbin, Richard M.; Smits, Miriam T.; Plasterk, Ronald H. A.

    1996-01-01

    We present an approach to map large numbers of Tc1 transposon insertions in the genome of Caenorhabditis elegans. Strains have been described that contain up to 500 polymorphic Tc1 insertions. From these we have cloned and shotgun sequenced over 2000 Tc1 flanks, resulting in an estimated set of 400 or more distinct Tc1 insertion alleles. Alignment of these sequences revealed a weak Tc1 insertion site consensus sequence that was symmetric around the invariant TA target site and reads CAYATATRTG. The Tc1 flanking sequences were compared with 40 Mbp of a C. elegans genome sequence. We found 151 insertions within the sequenced area, a density of ≈1 Tc1 insertion in every 265 kb. As the rest of the C. elegans genome sequence is obtained, remaining Tc1 alleles will fall into place. These mapped Tc1 insertions can serve two functions: (i) insertions in or near genes can be used to isolate deletion derivatives that have that gene mutated; and (ii) they represent a dense collection of polymorphic sequence-tagged sites. We demonstrate a strategy to use these Tc1 sequence-tagged sites in fine-mapping mutations. PMID:8962114

  12. Adipose tissue hyperplasia with enhanced adipocyte-derived stem cell activity in Tc1(C8orf4)-deleted mice

    PubMed Central

    Jang, Hayoung; Kim, Minsung; Lee, Soyoung; Kim, Jungtae; Woo, Dong-Cheol; Kim, Kyung Won; Song, Kyuyoung; Lee, Inchul

    2016-01-01

    Adipose tissue hyperplasia with increased number of adipocytes is implicated in a protective rather than deleterious effect on obesity-associated metabolic disorder. It is poorly understood how the adipose tissue cellularity is regulated. Tc1 is a gene of vertebrates that regulates diverse downstream genes. Young Tc1-deleted mice fed on standard chow diet show expanded adipose tissue with smaller adipocytes in size compared to wild type controls, representing adipose tissue hyperplasia. Tc1−/− mice show enhanced glucose tolerance and reduced serum lipids. Adipocyte-derived stem cells (ADSCs) from Tc1−/− mice show enhanced proliferative and adipogenic capacity compared to wild type controls, suggesting that the adipose hyperplasia is regulated at the stem cell level. PPARγ and CEBPα are up-regulated robustly in Tc1−/− ADSCs upon induction for adipogenesis. Wisp2 and Dlk1, inhibitors of adipogenesis, are down-regulated in Tc1−/− ADSCs compared to controls. Tc1-transfected NIH3T3 cells show higher β-catenin reporter signals than vector transfected controls, suggesting a role of canonical Wnt signaling in the Tc1-dependent adipose regulation. Our data support that Tc1 is a novel regulator for adipose stem cells. Adipose tissue hyperplasia may be implicated in the metabolic regulation of Tc1−/− mice. PMID:27775060

  13. Ex vivo rapamycin generates Th1/Tc1 or Th2/Tc2 Effector T cells with enhanced in vivo function and differential sensitivity to post-transplant rapamycin therapy.

    PubMed

    Jung, Unsu; Foley, Jason E; Erdmann, Andreas A; Toda, Yoko; Borenstein, Todd; Mariotti, Jacopo; Fowler, Daniel H

    2006-09-01

    Rapamycin prevention of murine graft-versus-host disease (GVHD) is associated with a shift toward Th2- and Tc2-type cytokines. Recently, we found that use of rapamycin during ex vivo donor Th2 cell generation enhances the ability of adoptively transferred Th2 cells to prevent murine GVHD. In this study, using a method, without antigen-presenting cells, of T-cell expansion based on CD3,CD28 costimulation, we evaluated whether (1) rapamycin preferentially promotes the generation of Th2/Tc2 cells relative to Th1/Tc1 cells, (2) rapamycin-generated T-cell subsets induce cytokine skewing after allogeneic bone marrow transplantation (BMT), and (3) such in vivo cytokine skewing is sensitive to post-BMT rapamycin therapy. Contrary to our hypothesis, rapamycin did not preferentially promote Th2/Tc2 cell polarity, because rapamycin-generated Th1/Tc1 cells secreted type I cytokines (interleukin [IL]-2 and interferon-gamma) did not secrete type II cytokines (IL-4, IL-5, IL-10, or IL-13) and mediated fasL-based cytolysis. Rapamycin influenced T-cell differentiation, because each of the Th1, Th2, Tc1, and Tc2 subsets generated in rapamycin had increased expression of the central-memory T-cell marker, L-selectin (CD62L). Rapamycin-generated Th1/Tc1 and Th2/Tc2 cells were not anergic but instead had increased expansion after costimulation in vitro, increased expansion in vivo after BMT, and maintained full capacity to skew toward type I or II cytokines after BMT, respectively; further, rapamycin-generated Th1/Tc1 cells mediated increased lethal GVHD relative to control Th1/Tc1 cells. Rapamycin therapy after BMT in recipients of rapamycin-generated Th1/Tc1 cells greatly reduced Th1/Tc1 cell number, greatly reduced type I cytokines, and reduced lethal GVHD; in marked contrast, rapamycin therapy in recipients of rapamycin-generated Th2/Tc2 cells nominally influenced the number of Th2/Tc2 cells in vivo and did not abrogate post-BMT type II cytokine skewing. In conclusion, ex vivo and

  14. Protein profiles in Tc1 mice implicate novel pathway perturbations in the Down syndrome brain.

    PubMed

    Ahmed, Md Mahiuddin; Dhanasekaran, A Ranjitha; Tong, Suhong; Wiseman, Frances K; Fisher, Elizabeth M C; Tybulewicz, Victor L J; Gardiner, Katheleen J

    2013-05-01

    Tc1 mouse model of Down syndrome (DS) is functionally trisomic for ∼120 human chromosome 21 (HSA21) classical protein-coding genes. Tc1 mice display features relevant to the DS phenotype, including abnormalities in learning and memory and synaptic plasticity. To determine the molecular basis for the phenotypic features, the levels of 90 phosphorylation-specific and phosphorylation-independent proteins were measured by Reverse Phase Protein Arrays in hippocampus and cortex, and 64 in cerebellum, of Tc1 mice and littermate controls. Abnormal levels of proteins involved in MAP kinase, mTOR, GSK3B and neuregulin signaling were identified in trisomic mice. In addition, altered correlations among the levels of N-methyl-D-aspartate (NMDA) receptor subunits and the HSA21 proteins amyloid beta (A4) precursor protein (APP) and TIAM1, and between immediate early gene (IEG) proteins and the HSA21 protein superoxide dismutase-1 (SOD1) were found in the hippocampus of Tc1 mice, suggesting altered stoichiometry among these sets of functionally interacting proteins. Protein abnormalities in Tc1 mice were compared with the results of a similar analysis of Ts65Dn mice, a DS mouse model that is trisomic for orthologs of 50 genes trisomic in the Tc1 plus an additional 38 HSA21 orthologs. While there are similarities, abnormalities unique to the Tc1 include increased levels of the S100B calcium-binding protein, mTOR proteins RAPTOR and P70S6, the AMP-kinase catalytic subunit AMPKA, the IEG proteins FBJ murine osteosarcoma viral oncogene homolog (CFOS) and activity-regulated cytoskeleton-associated protein (ARC), and the neuregulin 1 receptor ERBB4. These data identify novel perturbations, relevant to neurological function and to some seen in Alzheimer's disease, that may occur in the DS brain, potentially contributing to phenotypic features and influencing drug responses.

  15. Evaluation of the Allergenicity Potential of TcPR-10 Protein from Theobroma cacao

    PubMed Central

    Cardoso, Thyago Hermylly Santana; Pirovani, Carlos Priminho; Micheli, Fabienne; Noronha, Fátima Soares Motta; Alves, Andréa Catão; Faria, Ana Maria Caetano; da Silva Gesteira, Abelmon

    2012-01-01

    Background The pathogenesis related protein PR10 (TcPR-10), obtained from the Theobroma cacao-Moniliophthora perniciosa interaction library, presents antifungal activity against M. perniciosa and acts in vitro as a ribonuclease. However, despite its biotechnological potential, the TcPR-10 has the P-loop motif similar to those of some allergenic proteins such as Bet v 1 (Betula verrucosa) and Pru av 1 (Prunus avium). The insertion of mutations in this motif can produce proteins with reduced allergenic power. The objective of the present work was to evaluate the allergenic potential of the wild type and mutant recombinant TcPR-10 using bioinformatics tools and immunological assays. Methodology/Principal Findings Mutant substitutions (T10P, I30V, H45S) were inserted in the TcPR-10 gene by site-directed mutagenesis, cloned into pET28a and expressed in Escherichia coli BL21(DE3) cells. Changes in molecular surface caused by the mutant substitutions was evaluated by comparative protein modeling using the three-dimensional structure of the major cherry allergen, Pru av 1 as a template. The immunological assays were carried out in 8–12 week old female BALB/c mice. The mice were sensitized with the proteins (wild type and mutants) via subcutaneous and challenged intranasal for induction of allergic airway inflammation. Conclusions/Significance We showed that the wild TcPR-10 protein has allergenic potential, whereas the insertion of mutations produced proteins with reduced capacity of IgE production and cellular infiltration in the lungs. On the other hand, in vitro assays show that the TcPR-10 mutants still present antifungal and ribonuclease activity against M. perniciosa RNA. In conclusion, the mutant proteins present less allergenic potential than the wild TcPR-10, without the loss of interesting biotechnological properties. PMID:22768037

  16. Evaluating {sup 99m}Tc Auger electrons for targeted tumor radiotherapy by computational methods

    SciTech Connect

    Tavares, Adriana Alexandre S.; Tavares, Joao Manuel R. S.

    2010-07-15

    Purpose: Technetium-99m ({sup 99m}Tc) has been widely used as an imaging agent but only recently has been considered for therapeutic applications. This study aims to analyze the potential use of {sup 99m}Tc Auger electrons for targeted tumor radiotherapy by evaluating the DNA damage and its probability of correct repair and by studying the cellular kinetics, following {sup 99m}Tc Auger electron irradiation in comparison to iodine-131 ({sup 131}I) beta minus particles and astatine-211 ({sup 211}At) alpha particle irradiation. Methods: Computational models were used to estimate the yield of DNA damage (fast Monte Carlo damage algorithm), the probability of correct repair (Monte Carlo excision repair algorithm), and cell kinetic effects (virtual cell radiobiology algorithm) after irradiation with the selected particles. Results: The results obtained with the algorithms used suggested that {sup 99m}Tc CKMMX (all M-shell Coster-Kroning--CK--and super-CK transitions) electrons and Auger MXY (all M-shell Auger transitions) have a therapeutic potential comparable to high linear energy transfer {sup 211}At alpha particles and higher than {sup 131}I beta minus particles. All the other {sup 99m}Tc electrons had a therapeutic potential similar to {sup 131}I beta minus particles. Conclusions: {sup 99m}Tc CKMMX electrons and Auger MXY presented a higher probability to induce apoptosis than {sup 131}I beta minus particles and a probability similar to {sup 211}At alpha particles. Based on the results here, {sup 99m}Tc CKMMX electrons and Auger MXY are useful electrons for targeted tumor radiotherapy.

  17. Transgenic maize event TC1507: Global status of food, feed, and environmental safety

    PubMed Central

    Baktavachalam, Gajendra B; Delaney, Bryan; Fisher, Tracey L; Ladics, Gregory S; Layton, Raymond J; Locke, Mary EH; Schmidt, Jean; Anderson, Jennifer A; Weber, Natalie N; Herman, Rod A; Evans, Steven L

    2015-01-01

    Maize (Zea mays) is a widely cultivated cereal that has been safely consumed by humans and animals for centuries. Transgenic or genetically engineered insect-resistant and herbicide-tolerant maize, are commercially grown on a broad scale. Event TC1507 (OECD unique identifier: DAS-Ø15Ø7–1) or the Herculex®# I trait, an insect-resistant and herbicide-tolerant maize expressing Cry1F and PAT proteins, has been registered for commercial cultivation in the US since 2001. A science-based safety assessment was conducted on TC1507 prior to commercialization. The safety assessment addressed allergenicity; acute oral toxicity; subchronic toxicity; substantial equivalence with conventional comparators, as well as environmental impact. Results from biochemical, physicochemical, and in silico investigations supported the conclusion that Cry1F and PAT proteins are unlikely to be either allergenic or toxic to humans. Also, findings from toxicological and animal feeding studies supported that maize with TC1507 is as safe and nutritious as conventional maize. Maize with TC1507 is not expected to behave differently than conventional maize in terms of its potential for invasiveness, gene flow to wild and weedy relatives, or impact on non-target organisms. These safety conclusions regarding TC1507 were acknowledged by over 20 regulatory agencies including United States Environment Protection Agency (US EPA), US Department of Agriculture (USDA), Canadian Food Inspection Agency (CFIA), and European Food Safety Authority (EFSA) before authorizing cultivation and/or food and feed uses. A comprehensive review of the safety studies on TC1507, as well as some benefits, are presented here to serve as a reference for regulatory agencies and decision makers in other countries where authorization of TC1507 is or will be pursued. PMID:26018138

  18. Expression of an endoglucanase from Tribolium castaneum (TcEG1) in Saccharomyces cerevisiae.

    PubMed

    Shirley, Derek; Oppert, Cris; Reynolds, Todd B; Miracle, Bethany; Oppert, Brenda; Klingeman, William E; Jurat-Fuentes, Juan Luis

    2014-10-01

    Insects are a largely unexploited resource in prospecting for novel cellulolytic enzymes to improve the production of ethanol fuel from lignocellulosic biomass. The cost of lignocellulosic ethanol production is expected to decrease by the combination of cellulose degradation (saccharification) and fermentation of the resulting glucose to ethanol in a single process, catalyzed by the yeast Saccharomyces cerevisiae transformed to express efficient cellulases. While S. cerevisiae is an established heterologous expression system, there are no available data on the functional expression of insect cellulolytic enzymes for this species. To address this knowledge gap, S. cerevisiae was transformed to express the full-length cDNA encoding an endoglucanase from the red flour beetle, Tribolium castaneum (TcEG1), and evaluated the activity of the transgenic product (rTcEG1). Expression of the TcEG1 cDNA in S. cerevisiae was under control of the strong glyceraldehyde-3 phosphate dehydrogenase promoter. Cultured transformed yeast secreted rTcEG1 protein as a functional β-1,4-endoglucanase, which allowed transformants to survive on selective media containing cellulose as the only available carbon source. Evaluation of substrate specificity for secreted rTcEG1 demonstrated endoglucanase activity, although some activity was also detected against complex cellulose substrates. Potentially relevant to uses in biofuel production rTcEG1 activity increased with pH conditions, with the highest activity detected at pH 12. Our results demonstrate the potential for functional production of an insect cellulase in S. cerevisiae and confirm the stability of rTcEG1 activity in strong alkaline environments.

  19. Transgenic maize event TC1507: Global status of food, feed, and environmental safety.

    PubMed

    Baktavachalam, Gajendra B; Delaney, Bryan; Fisher, Tracey L; Ladics, Gregory S; Layton, Raymond J; Locke, Mary Eh; Schmidt, Jean; Anderson, Jennifer A; Weber, Natalie N; Herman, Rod A; Evans, Steven L

    2015-01-01

    Maize (Zea mays) is a widely cultivated cereal that has been safely consumed by humans and animals for centuries. Transgenic or genetically engineered insect-resistant and herbicide-tolerant maize, are commercially grown on a broad scale. Event TC1507 (OECD unique identifier: DAS-Ø15Ø7-1) or the Herculex®(#) I trait, an insect-resistant and herbicide-tolerant maize expressing Cry1F and PAT proteins, has been registered for commercial cultivation in the US since 2001. A science-based safety assessment was conducted on TC1507 prior to commercialization. The safety assessment addressed allergenicity; acute oral toxicity; subchronic toxicity; substantial equivalence with conventional comparators, as well as environmental impact. Results from biochemical, physicochemical, and in silico investigations supported the conclusion that Cry1F and PAT proteins are unlikely to be either allergenic or toxic to humans. Also, findings from toxicological and animal feeding studies supported that maize with TC1507 is as safe and nutritious as conventional maize. Maize with TC1507 is not expected to behave differently than conventional maize in terms of its potential for invasiveness, gene flow to wild and weedy relatives, or impact on non-target organisms. These safety conclusions regarding TC1507 were acknowledged by over 20 regulatory agencies including United States Environment Protection Agency (US EPA), US Department of Agriculture (USDA), Canadian Food Inspection Agency (CFIA), and European Food Safety Authority (EFSA) before authorizing cultivation and/or food and feed uses. A comprehensive review of the safety studies on TC1507, as well as some benefits, are presented here to serve as a reference for regulatory agencies and decision makers in other countries where authorization of TC1507 is or will be pursued.

  20. Evaluation of Tc-99m (V) DMSA binding to human plasma proteins.

    PubMed

    Lee, Bi-Fang; Yeh, Jwu-Lai; Chiu, Nan-Tsing; Liu, Gin-Chung; Yu, Hsin-Su; Wang, Mei-Hui; Shen, Lie-Hang

    2008-01-01

    As a critical step toward elucidating the mechanism of localization of Tc-99m (V) dimercaptosuccinic acid (DMSA), we investigated its binding and transport in blood in comparison with Ga-67 citrate. The studies were performed in vitro by incubating Tc-99m (V) DMSA with blood (one sample at 4 degrees Celcius and another at 37 degrees Celcius) to assess its binding to plasma proteins using ultrafiltration, dialysis, electrophoresis, gel filtration chromatography and affinity chromatography. A parallel experiment for determining the blood binding of Ga-67 citrate was performed using the same procedures. Using ultrafiltration, dialysis, electrophoresis and gel filtration chromatography, labeled plasma samples showed that protein binding for Tc-99m (V) DMSA was 45-54% at 37 degrees Celcius and 73-80% at 4 degrees Celcius. The figures for Ga-67 citrate were 43-53% at 37 degrees Celcius and 75-81% at 4 degrees Celcius. Electrophoresis showed that Tc-99m (V) DMSA was mostly bound to plasma albumin (36.05 +/- 2.48% at 37 degrees Celcius and 60.04 +/- 1.87% at 4 degrees Celcius), and that the proportion of Ga-67 radioactivity associated with beta-globulin was 34.23 +/- 1.37% at 37 degrees Celcius and 55.71 +/- 3.69% at 4 degrees Celcius. In affinity chromatography experiments, Tc-99m (V) DMSA did not bind to transferrin, unlike Ga-67 citrate. This study demonstrates that, at the radiopharmaceutical tracer level, most Tc-99m (V) DMSA in blood is protein-bound, primarily to albumin, but not to transferrin. In contrast, Ga-67 citrate was bound primarily to transferrin. The knowledge that albumin is the main transport protein of Tc-99m (V) DMSA may contribute to a better understanding of its biodistribution and pharmacokinetics.

  1. Effect of Van Hove singularities on high-Tc superconductivity in H3S

    NASA Astrophysics Data System (ADS)

    Sano, Wataru; Koretsune, Takashi; Tadano, Terumasa; Akashi, Ryosuke; Arita, Ryotaro

    2016-03-01

    One of the interesting open questions for the high-transition-temperature (Tc) superconductivity in sulfur hydrides is why high-pressure phases of H3S have extremely high Tc's. Recently, it has been pointed out that the presence of the Van Hove singularities (VHS) around the Fermi level is crucial. However, while there have been quantitative estimates of Tc based on the Migdal-Eliashberg theory, the energy dependence of the density of states (DOS) has been neglected to simplify the Eliashberg equation. In this study, we go beyond the constant DOS approximation and explicitly consider the electronic structure over 40 eV around the Fermi level. In contrast with the previous conventional calculations, this approach with a sufficiently large number of Matsubara frequencies enables us to calculate Tc without introducing the empirical pseudo Coulomb potential. We show that while H3S has much higher Tc than H2S for which the VHS is absent, the constant DOS approximation employed so far seriously overestimates (underestimates) Tc by ˜60 K (˜10 K) for H3S (H2S ). We then discuss the impact of the strong electron-phonon coupling on the electronic structure with and without the VHS and how it affects the superconductivity. In particular, we focus on (1) the feedback effect in the self-consistent calculation of the self-energy, (2) the effect of the energy shift due to the zero-point motion, and (3) the effect of the changes in the phonon frequencies due to strong anharmonicity. We show that the effect of (1)-(3) on Tc is about 10-30 K for both H3S and H2S . Eventually, Tc is estimated to be 181 K for H3S at 250 GPa and 34 K for H2S at 140 GPa, which explains the pressure dependence of Tc observed in the experiment. In addition, we evaluate the lowest-order vertex correction beyond the Migdal-Eliashberg theory and discuss the validity of the Migdal approximation for sulfur hydrides.

  2. Immune Protection against Trypanosoma cruzi Induced by TcVac4 in a Canine Model

    PubMed Central

    Aparicio-Burgos, José E.; Zepeda-Escobar, José A.; de Oca-Jimenez, Roberto Montes; Estrada-Franco, José G.; Barbabosa-Pliego, Alberto; Ochoa-García, Laucel; Alejandre-Aguilar, Ricardo; Rivas, Nancy; Peñuelas-Rivas, Giovanna; Val-Arreola, Margarita; Gupta, Shivali; Salazar-García, Felix; Garg, Nisha J.; Vázquez-Chagoyán, Juan C.

    2015-01-01

    Chagas disease, caused by Trypanosoma cruzi, is endemic in southern parts of the American continent. Herein, we have tested the protective efficacy of a DNA-prime/T. rangeli-boost (TcVac4) vaccine in a dog (Canis familiaris) model. Dogs were immunized with two-doses of DNA vaccine (pcDNA3.1 encoding TcG1, TcG2, and TcG4 antigens plus IL-12- and GM-CSF-encoding plasmids) followed by two doses of glutaraldehyde-inactivated T. rangeli epimastigotes (TrIE); and challenged with highly pathogenic T. cruzi (SylvioX10/4) isolate. Dogs given TrIE or empty pcDNA3.1 were used as controls. We monitored post-vaccination and post-challenge infection antibody response by an ELISA, parasitemia by blood analysis and xenodiagnosis, and heart function by electrocardiography. Post-mortem anatomic and pathologic evaluation of the heart was conducted. TcVac4 induced a strong IgG response (IgG2>IgG1) that was significantly expanded post-infection, and moved to a nearly balanced IgG2/IgG1 response in chronic phase. In comparison, dogs given TrIE or empty plasmid DNA only developed high IgG titers with IgG2 predominance in response to T. cruzi infection. Blood parasitemia, tissue parasite foci, parasite transmission to triatomines, electrocardiographic abnormalities were significantly lower in TcVac4-vaccinated dogs than was observed in dogs given TrIE or empty plasmid DNA only. Macroscopic and microscopic alterations, the hallmarks of chronic Chagas disease, were significantly decreased in the myocardium of TcVac4-vaccinated dogs. We conclude that TcVac4 induced immunity was beneficial in providing resistance to T. cruzi infection, evidenced by control of chronic pathology of the heart and preservation of cardiac function in dogs. Additionally, TcVac4 vaccination decreased the transmission of parasites from vaccinated/infected animals to triatomines. PMID:25853654

  3. Serum-mediated activation of macrophages reflects TcVac2 vaccine efficacy against Chagas disease.

    PubMed

    Gupta, Shivali; Silva, Trevor S; Osizugbo, Jessica E; Tucker, Laura; Spratt, Heidi M; Garg, Nisha J

    2014-04-01

    Chagas disease is endemic in Latin America and an emerging infectious disease in the United States. No effective treatments are available. The TcG1, TcG2, and TcG4 antigens are highly conserved in clinically relevant Trypanosoma cruzi isolates and are recognized by B and T cells in infected hosts. Delivery of these antigens as a DNA prime/protein boost vaccine (TcVac2) elicited lytic antibodies and type 1 CD8(+) T cells that expanded upon challenge infection and provided >90% control of parasite burden and myocarditis in chagasic mice. Here we determined if peripheral blood can be utilized to capture the TcVac2-induced protection from Chagas disease. We evaluated the serum levels of T. cruzi kinetoplast DNA (TckDNA), T. cruzi 18S ribosomal DNA (Tc18SrDNA), and murine mitochondrial DNA (mtDNA) as indicators of parasite persistence and tissue damage and monitored the effect of sera on macrophage phenotype. Circulating TckDNA/Tc18SrDNA and mtDNA were decreased by >3- to 5-fold and 2-fold, respectively, in vaccinated infected mice compared to nonvaccinated infected mice. Macrophages incubated with sera from vaccinated infected mice exhibited M2 surface markers (CD16, CD32, CD200, and CD206), moderate proliferation, a low oxidative/nitrosative burst, and a regulatory/anti-inflammatory cytokine response (interleukin-4 [IL-4] plus IL-10 > tumor necrosis factor alpha [TNF-α]). In comparison, macrophages incubated with sera from nonvaccinated infected mice exhibited M1 surface markers, vigorous proliferation, a substantial oxidative/nitrosative burst, and a proinflammatory cytokine response (TNF-α ≫ IL-4 plus IL-10). Cardiac infiltration of macrophages and TNF-α and oxidant levels were significantly reduced in TcVac2-immunized chagasic mice. We conclude that circulating TcDNA and mtDNA levels and macrophage phenotype mediated by serum constituents reflect in vivo levels of parasite persistence, tissue damage, and inflammatory/anti-inflammatory state and have potential

  4. The unusually high Tc in rare-earth-doped single crystalline CaFe2As2

    NASA Astrophysics Data System (ADS)

    Wei, Fengyan; Lv, Bing; Deng, Liangzi; Meen, James K.; Xue, Yu-Yi; Chu, Ching-Wu

    2014-08-01

    In rare-earth-doped single crystalline CaFe2As2, the mysterious small volume fraction which superconducts up to 49 K, much higher than the bulk Tc ~ 30 s K, has prompted a long search for a hidden variable that could enhance the Tc by more than 30% in iron-based superconductors of the same structure. Here we report a chemical, structural and magnetic study of CaFe2As2 systematically doped with La, Ce, Pr and Nd. Coincident with the high Tc phase, we find extreme magnetic anisotropy, accompanied by an unexpected doping-independent Tc and equally unexpected superparamagnetic clusters associated with As vacancies. These observations lead us to conjecture that the tantalizing Tc enhancement may be associated with naturally occurring chemical interfaces and may thus provide a new paradigm in the search for superconductors with higher Tc.

  5. The role of 99mTc(V)-DMSA scan as compared to 99mTc-MDP and CT scans in imaging the primary tumor and metastases of osteosarcoma.

    PubMed

    Zissimopoulos, Athanassios; Zanglis, Antonios; Andreopoulos, Dimitrios; Baziotis, Nikolaos

    2005-01-01

    The oncophilic complex of technetium-99m labeled pentavalent dimercaptosuccinic acid (99mTc(V)-DMSA) has been successfully used for the detection of primary and metastatic medullary thyroid cancer and for imaging various soft tissue tumors like lung, brain and prostate cancer. In this article, the role of 99mTc(V)-DMSA in the diagnosis of the primary tumor and metastases of osteosarcoma patients as compared to the 99mTc-MDP scan and the CT scan was studied. Twenty-eight patients with bone disease were referred to the Nuclear Medicine Department of Saint Savas Oncology Hospital in Athens from the Orthopedics Department of the same Hospital. From them, 18 (Group A) had osteosarcoma, 7 (Group B) osteomyelitis and 3 (Group C) bone fractures. The final diagnosis was made after fine needle aspiration biopsy. All patients were subjected to the 99mTc(V)-DMSA scan, the standard bone scan (99mTc-MDP) and CT scan. Group A patients showed a selective uptake of 99mTc(V)-DMSA in the primary tumor region. No abnormal 99mTc(V)-DMSA uptake was observed in the patients of Groups B and C. The 99mTc(V)-DMSA scan was found to be superior to the 99mTc-MDP and the CT scans in identifying metastases of osteosarcoma. Sensitivity was 100%, 86% and 98% respectively.

  6. Vesicoureteral Reflux Detected with 99mTc-DTPA Renal Scintigraphy during Evaluation of Renal Function

    PubMed Central

    Manevska, Nevena; Stojanoski, Sinisa; Majstorov, Venjamin; Pop-Gjorcheva, Daniela; Zdraveska, Nikolina; Kuzmanovska, Dafina

    2016-01-01

    BACKGROUND: Radionuclide techniques, as direct radionuclide cystography and 99mTc-DMSA scintigraphy, have been used in evaluation of vesicoureteral reflux (VUR) and reflux nephropathy (RN) in children. Dynamic 99mTc-DTPA scintigraphy is reserved for evaluation of differential renal function and obstruction in children, where hydronephrosis is detected by ultrasonography (US) pre- or postnatally. CASE REPORT: Six year old boy was prenatally diagnosed with bilateral hydronephrosis. Postnatal, severe bilateral VUR was detected by voiding urethrocytography. US and 99mTc-DTPA scintigraphy performed in the first month of life showed small left kidney that participated with 2% in the global renal function. Bilateral cutaneous ureterostomy has been performed in order to obtain good renal drainage and promote optimal renal growth. Twelve months later, classic antireflux procedure was done. Control 99mTc-DTPA scintigraphy, 5 ys after antireflux surgery, revealed persisting radioactivity during the diuretic phase, in the left kidney that indicated antireflux procedure failure with VUR reappearance. CONCLUSION: 99mTc-DTPA scintigraphy is the first method of choice for long-term monitoring of individual kidney function in children with VUR and other congenital urinary tract anomalies. Additionally, it can be used as indirect radionuclide cystography when rising of radioactivity in the kidney region, during the diuretic phase can indicate presence of VUR. PMID:27275347

  7. Family of Tc1-like elements from fish genomes and horizontal transfer.

    PubMed

    Pocwierz-Kotus, Anita; Burzynski, Artur; Wenne, Roman

    2007-04-01

    The involvement of horizontal transfer (HT) in the evolution of vertebrate transposable elements (TEs) is a matter of an ongoing debate. The phylogenetic relationships between Tc1 TEs, based on limited dataset have been previously used to infer a case of Tc1 HT between the genomes of fish and frogs. Here this hypothesis has been critically evaluated by the experimental approach including comparative data on the range of fish species available today. The distribution of a Tc1 subfamily of TE in selected fish species was investigated by PCR with a single primer complementary to ITRs and showed that they are widespread in the studied 17 fish species. They belong to five different subfamilies of Tc1 TEs, as revealed by the comparison with current genomic data for fish and amphibians. The original hypothesis would get much weaker support from the current data, although at least one novel potential and more convincing case of HT was identified between genomes of Perciformes fish. An interesting case of recombination-driven mobilisation of a degenerated TE by distantly related TE from different subfamily was discovered in the genome of pike. The occurrence of such cases widens the range of TE elements identifiable with the employed experimental approach. Further similar studies would help to explain the evolution of the multiple Tc1 lineages including species for which full genome sequences will not be available soon.

  8. Technetium-99m galactosyl-neoglycoalbumin (Tc-NGA) liver imaging: Application in liver transplantation

    SciTech Connect

    Woodle, E.S.; Ward, R.E.; Vera, D.R.; Stadalnik, R.C.

    1985-05-01

    Tc-NGA is a new liver imaging agent which binds to hepatic binding protein (HBP), a hepatocyte-specific membrane receptor. The purpose of the present study was to evaluate the potential role of Tc-NGA imaging in liver transplantation. The molar Tc-NGA dose was standardized according to patient weight (0.7 nmole/kg). After a 30 minute dynamic imaging study (5 mCi, IV), kinetic analysis of time activity data (heart, liver), provided values for receptor concentration, (HBP), and hepatic blood flow, Q. Eleven Tc-NGA imaging studies were performed in transplant candidates and 22 studies were performed in seven transplant recipients. Preservation damage was manifested by diffuse patchiness in tracer distribution which resolved during the following two weeks. Histologically proven, localized hepatic infarcts were demonstrated in three recipients. Lobar infarction was demonstrated in one recipient. Hepatic regeneration was later demonstrated in this patient after hepatic lobectomy. Hepatic blood flow was markedly decreased in the early postoperative period, but improved with time. Increased (HBP) was demonstrated with regeneration. Markedly decreased (HBP) and Q were obtained in several candidates who died awaiting transplantation. These studies indicate that TC-NGA liver imaging provides a valuable new means for: (1) evaluation of preservation damage, (2) early demonstration of hepatic infarction, (3) evaluation of hepatic rejection, and (4) selection of patients for hepatic transplantation.

  9. Modelling 99Tc concentrations in Fucus vesiculosus from the north-east Irish Sea.

    PubMed

    Nawakowski, Claire; Nicholson, Michael D; Kershaw, Peter John; Leonard, Kinson S

    2004-01-01

    In 1994 there were substantial increases in the quantity of 99Tc discharged into the north-east Irish Sea from BNFL Sellafield (UK), concomitant with improvements in waste treatment procedures. As a consequence, the concentration of 99Tc observed in seawater and biota samples, taken from the Irish Sea coastline, increased significantly. Elevated concentrations were also reported in Dutch, Danish, Norwegian, Swedish and Arctic waters in subsequent years. In the present study a simple numerical model was developed and applied to time-series data of 99Tc concentrations in the brown seaweed Fucus vesiculosus, collected from three UK sites in the vicinity of Sellafield (St. Bees, Heysham, Port William). The model considered site-specific scaling effects, lag times, previous discharge history and potential seasonal variation in uptake. In general, there was a good fit between predicted and observed concentrations, but the degree of uncertainty varied inversely with the frequency of sampling. We did not observe a significant seasonal variation. The modelled lag times to the three sites were consistent with transport times based on observations of the water column distribution of 99Tc. The model was applied to a variety of discharge scenarios, reflecting current discussion on the future management of 99Tc releases. Concentrations in Fucus reached asymptotic values in 3-10 years, depending on the scenario and sampling site under consideration.

  10. Valence effects on solubility and sorption: the solubility of Tc(IV) oxides

    SciTech Connect

    Meyer, R.E.; Arnold, W.D.; Case, F.I.

    1986-03-01

    The solubilities of technetium (IV) oxides have been determined in solutions of NaCl, HCl, and synthetic groundwaters in the pH range 0 to 10. Oxides were prepared either by electroreduction from Tc(VII) solutions onto platinum electrodes or by precipitation of Tc from Tc(VII) solutions using hydrazine. In some of the determinations, the oxide was precipitated onto purified sand by use of hydrazine. The oxide-covered sand was then placed into a column and the test solution continuously recirculated through the column. The oxide plated on platinum was placed into a small cell and the test solution stirred. Solubilities were determined by measuring the beta radiation of /sup 99/Tc in the stirred or circulated solution in contact with the oxide. In the pH range 4 to 10, solubilities were in the range 7.5 x 10/sup -9/ to 5 x 10/sup -8/ mol/L, and most of the determinations were in the range 1 x 10/sup -8/ to 2 x 10/sup -8/ mol/L. In acid solutions the solubilities were generally higher for hydrazine-precipitated oxide than for the electrodeposited oxide, and they increased as the pH was lowered. Solubilities of Tc(IV) oxides will be useful for calculation of transport rates of technetium for the case of solubility-limited transport in nuclear waste repository environments.

  11. Biodistribution and pharmacokinetics of the (99m)Tc labeled human elastase inhibitor, elafin, in rats.

    PubMed

    Kaschwich, Mark; Lützen, Ulf; Zhao, Yi; Tjiong, Angelina; Marx, Marlies; Haenisch, Sierk; Wiedow, Oliver; Preuss, Stefanie; Culman, Juraj; Zuhayra, Maaz

    2016-04-01

    Elafin is a potent reversible inhibitor of the pro-inflammatory proteases leukocyte elastase and protease 3. It is currently in clinical development for the use in postoperative inflammatory diseases. We investigated the pharmacokinetics of (99m)Tc-labeled elafin ((99m)Tc-Elafin) in blood and individual organs in rat after bolus intravenous injection using the single photon emission tomography (SPECT). (99m)Tc-Elafin predominantly accumulated in the kidney reaching a maximum of 8.5% ± 0.1% of the injected dose per gram (ID/g) at 5 min post injection (p.i) and decreased only slowly during 24 h. In contrast, the initially high radio activity recorded in the other organs rapidly decreased parallel to the radioactivity detected in blood. The blood kinetics fits to a two compartment kinetics model. The radio activity in the dissected kidney was 4.98 ± 1.24%ID/g 24 h p.i, while in other organs, including the brain, no accumulation of (99m)Tc-Elafin was detected. At this time point 30% of the detected radioactivity in the kidney was identified to be not metabolized (99m)Tc-Elafin. In conclusion, the blood and organ-specific kinetic data provide a basis for planning of adequate dosing regimens and the high accumulation of intact elafin in the kidney favors clinical developments targeting inflammatory kidney diseases, such as chronic allograft nephropathy after kidney transplantation.

  12. Characteristic two-dimensional Fermi surface topology of high-Tc iron-based superconductors.

    PubMed

    Sunagawa, Masanori; Ishiga, Toshihiko; Tsubota, Koji; Jabuchi, Taihei; Sonoyama, Junki; Iba, Keita; Kudo, Kazutaka; Nohara, Minoru; Ono, Kanta; Kumigashira, Hiroshi; Matsushita, Tomohiro; Arita, Masashi; Shimada, Kenya; Namatame, Hirofumi; Taniguchi, Masaki; Wakita, Takanori; Muraoka, Yuji; Yokoya, Takayoshi

    2014-03-14

    Unconventional Cooper pairing originating from spin or orbital fluctuations has been proposed for iron-based superconductors. Such pairing may be enhanced by quasi-nesting of two-dimensional electron and hole-like Fermi surfaces (FS), which is considered an important ingredient for superconductivity at high critical temperatures (high-Tc). However, the dimensionality of the FS varies for hole and electron-doped systems, so the precise importance of this feature for high-Tc materials remains unclear. Here we demonstrate a phase of electron-doped CaFe2As2 (La and P co-doped CaFe2As2) with Tc = 45 K, which is the highest Tc found for the AEFe2As2 bulk superconductors (122-type; AE = Alkaline Earth), possesses only cylindrical hole- and electron-like FSs. This result indicates that FS topology consisting only of two-dimensional sheets is characteristic of both hole- and electron-doped 122-type high-Tc superconductors.

  13. A New Piece in the High Tc Superconductivity Puzzle: Fe based Superconductors

    NASA Astrophysics Data System (ADS)

    Moreo, Adriana

    2011-10-01

    An overview of the historic and current developments in superconductivity will be be presented. The phenomenon of superconductivity was discovered almost 100 hundred years ago and it is still one of the hottest research topics providing fascinating puzzles and challenges to both theoreticians and experimentalists. There was a lag of almost 50 years between the experimental discovery of (low Tc) superconductivity and the development of the BCS theory which explained the phenomenon in terms of pairs of electrons held together by the interaction with the phonons in the material. The quest to discover superconducting materials with higher Tc's continued quietly for many years until huge progress occurred in the 1980' when Tc's higher than 77K were observed in copper-oxide based materials. The study of these new materials generated tremendous advances in both experimental and theoretical methods and much is now known about their properties; but the mechanism, i.e., the ``glue,'' that binds the electrons together is still unknown; it appears that phonons are unable to do the job and there is controversy on whether the magnetism present in these materials helps or hurts. Very recently, in 2008, high Tc was discovered in a new family of iron based materials. While they are similar to the cuprates in some ways, i.e., magnetism is present, there are many differences as well. This discovery provides a new chance to unveil the high-Tc mystery and the condensed matter community is intensely working on the subject.

  14. /sup 99m/Tc diphosphonate imaging in the differential diagnosis of thyroid nodules

    SciTech Connect

    Siddiqui, A.R.; Wellman, H.N.; Park, H.M.; Burney, B.T.

    1982-08-01

    Early /sup 99m/Tc diphosphonate (DP) imaging was performed in 122 patients with cold thyroid nodules in an effort to differentiate benign nodules from malignant. Immediately upon completion of the routine 24-hour /sup 123/I uptake and multiview pinhole imaging, /sup 99m/Tc DP was injected intravenously and three serial 3-minute anterior images of the thyroid gland were obtained. Follow-up information was available in 85 patients. All cystic lesions had less /sup 99m/Tc uptake as compared with the uptake in the normal parts of the thyroid. However, 48 of 50 solid nodules had /sup 99m/Tc DP uptake to the same or greater degree than did the normal gland. The other two had mixed pattern on ultrasound examination. Most of the carcinomas (8 of 10) and benign adenomas (15 of 22) had identical appearance on /sup 99m/Tc scans, i.e., uptake in the lesion being the same as in the normal thyroid. It appears that by using this technique it is possible to separate solid nodules from cystic, but not benign from malignant.

  15. Transport coefficients of heavy quarks around Tc at finite quark chemical potential

    NASA Astrophysics Data System (ADS)

    Berrehrah, H.; Gossiaux, P. B.; Aichelin, J.; Cassing, W.; Torres-Rincon, J. M.; Bratkovskaya, E.

    2014-11-01

    The interactions of heavy quarks with the partonic environment at finite temperature T and finite quark chemical potential μq are investigated in terms of transport coefficients within the dynamical quasiparticle model (DQPM) designed to reproduce the lattice-QCD (lQCD) results (including the partonic equation of state) in thermodynamic equilibrium. These results are confronted with those of nuclear many-body calculations close to the critical temperature Tc. The hadronic and partonic spatial diffusion coefficients join smoothly and show a pronounced minimum around Tc at μq=0 as well as at finite μq. Close to and above Tc its absolute value matches the lQCD calculations for μq=0 . The smooth transition of the heavy-quark transport coefficients from the hadronic to the partonic medium corresponds to a crossover in line with lattice calculations, and differs substantially from perturbative-QCD calculations which show a large discontinuity at Tc. This indicates that in the vicinity of Tc dynamically dressed massive partons should be the effective degrees of freedom in the quark-gluon plasma.

  16. Imaging study of using radiopharmaceuticals labeled with cyclotron-produced 99mTc

    NASA Astrophysics Data System (ADS)

    Hou, X.; Tanguay, J.; Vuckovic, M.; Buckley, K.; Schaffer, P.; Bénard, F.; Ruth, T. J.; Celler, A.

    2016-12-01

    Cyclotron-produced 99mTc (CPTc) has been recognized as an attractive and practical substitution of reactor/generator based 99mTc. However, the small amount of 92-98Mo in the irradiation of enriched 100Mo could lead to the production of other radioactive technetium isotopes (Tc-impurities) which cannot be chemically separated. Thus, these impurities could contribute to patient dose and affect image quality. The potential radiation dose caused by these Tc-impurities produced using different targets, irradiation conditions, and corresponding to different injection times have been investigated, leading us to create dose-based limits of these parameters for producing clinically acceptable CPTc. However, image quality has been not considered. The aim of the present work is to provide a comprehensive and quantitative analysis of image quality for CPTc. The impact of Tc-impurities in CPTc on image resolution, background noise, and contrast is investigated by performing both Monte-Carlo simulations and phantom experiments. Various targets, irradiation, and acquisition conditions are employed for investigating the image-based limits of CPTc production parameters. Additionally, the relationship between patient dose and image quality of CPTc samples is studied. Only those samples which meet both dose- and image-based limits should be accepted in future clinical studies.

  17. Population pharmacokinetics of TC-5214, a nicotinic channel modulator, in phase I and II clinical studies.

    PubMed

    Xu, Hongmei; Henningsson, Anja; Alverlind, Sofie; Tummala, Raj; Toler, Steven; Beaver, Jessica S; Al-Huniti, Nidal

    2014-06-01

    TC-5214 (dexmecamylamine) is a nicotinic channel modulator that has previously been evaluated for treatment of major depression disorder (MDD) and is currently being evaluated by Targacept as a treatment for overactive bladder. A comprehensive population pharmacokinetic (POP PK) model of TC-5214 was developed using nonlinear mixed-effects modeling of pooled plasma concentration data from 6 early phase I studies in 179 healthy participants or patients with non-MDD and 1 phase II study in 68 MDD patients. Concentration-time profiles of TC-5214 after either single or multiple oral doses of TC-5214 was described by a one-compartment model with first-order absorption with lag time and first-order elimination. Covariate analysis revealed that creatinine clearance was a significant covariate on clearance and that body weight significantly influenced the central volume of distribution. The final model (with identified covariates) was used to simulate steady-state exposure for patients with impaired renal function. Results from forest plots reveal that patients with moderate to severe renal impairment or end stage renal disease are associated with significantly higher Cssmax and AUC compared to patients with normal renal function. The proposed final POP PK model could be employed in defining a TC-5214 dosage regimen in patients with impaired renal function.

  18. Temporal trends for 99Tc in Norwegian coastal environments and spatial distribution in the Barents Sea.

    PubMed

    Brown, J E; Iospje, M; Kolstad, K E; Lind, B; Rudjord, A L; Strand, P

    2002-01-01

    The objective of this study was to reassess 99Tc transit times and transfer factors, from Sellafield to northern Norway, and to determine the extent of 99Tc migration to the Barents Sea. Filtered seawater samples were collected on a monthly basis from Hillesøy, northern Norway, and in February 1999 from the Barents Sea. Results showed an increase in levels of 99Tc at Hillesøy where activity concentrations have increased from a baseline of 0.2-0.4Bq m(-3) to a maximum of 1.6 Bq m(-3). A transit time of 42 months and a transfer factor of 6Bq m(-3) per PBq a(-1) have been derived, using cross-correlation analysis. The current study predicts that future levels are unlikely to increase dramatically over the levels observed in 1998. Levels of 99Tc in the Barents Sea ranged from 0.2 Bq m(-3) to 1.1 Bq m(-3) showing the influence of new 99Tc inputs by early 1999.

  19. Ultrasonic study on Bi-based high-Tc superconductors with preferred orientations

    NASA Astrophysics Data System (ADS)

    Dong, Jian; Deng, Tingzhang; Li, Fengying; Yao, Yushu

    1990-07-01

    Ultrasonic experimental studies on Bi-based ceramic superconductors are reported. The specimens used in our experiments were hot pressed after sintering in air; therefore, a preferred orientation of the granules was obtained. The frequencies of ultrasound were about 10 MHz, both for longitudinal and for transverse waves. It has been found that anomalies in the attenuation coefficient and sound velocity occur near 220 K, in the range between 10 and 50 K above Tc, and at Tc, respectively. The investigation shows that the pretransition in the range between 10 and 50 K above Tc leads to a tendency of softness and instability in crystal lattice, and the superconducting transition is present on the background of a rapid decrease in attenuation with the decrease in temperature. It is believed that a strong superconducting fluctuation exists above Tc. The deformation-potential model for acoustic-phonon-electron interaction, which is the basis of BCS theory, may be unsuitable for the high-Tc superconductors. A model of superconductivity due to optical-phonon-electron coupling is suggested.

  20. Accumulation of 99mTc-low-density lipoprotein in human malignant glioma.

    PubMed Central

    Leppälä, J.; Kallio, M.; Nikula, T.; Nikkinen, P.; Liewendahl, K.; Jääskeläinen, J.; Savolainen, S.; Gylling, H.; Hiltunen, J.; Callaway, J.

    1995-01-01

    Low-density lipoprotein (LDL) uptake in gliomas was studied to find out if LDL has potential as a drug carrier of boron, especially for boron neutron capture therapy. Single photon emission tomography (SPET) was performed 2 h and 20 h after intravenous injection of autologous 99mTc-labelled LDL in four patients with untreated and five patients with recurrent glioma. 99mTc-LDL uptake was compared with the uptake of 99mTc-labelled human serum albumin (HSA), an established blood pool marker. The intra- and peritumoral distributions of radioactivity in the SPET images were not identical for radiolabelled LDL and HSA. The mean LDL tumour to brain ratio, determined from transversal SPET slices at 20 h post injection, was 1.5 in untreated and 2.2 in recurrent gliomas; the corresponding ratios for HSA were 1.6 and 3.4. The brain to blood ratio remained constant at 2 h and 20 h in both types of tumours. These data are not consistent with highly selective, homogeneous uptake of LDL in gliomas. However, the different tumoral distribution and rate of uptake of 99mTc-LDL, as compared with 99mTc-HSA, indicate that the uptake of LDL is different from that of HSA and that further studies on the mechanism of LDL uptake in glioma are warranted. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:7841057

  1. Decreased renal uptake of (99m)Tc-DMSA in patients with tubular proteinuria.

    PubMed

    Lee, Beom Hee; Lee, So Hee; Choi, Hyun Jin; Kang, Hee Gyung; Oh, So Won; Lee, Dong Soo; Ha, Il Soo; Choi, Yong; Cheong, Hae Il

    2009-11-01

    Although technetium-99m-dimercaptosuccinic acid ((99m)Tc-DMSA) renal scans are widely used to evaluate renal tubular mass function, the mechanism by which renal uptake of DMSA occurs is still the subject of debate. Patients with various proximal tubular disorders show markedly decreased renal DMSA uptake, even when there is normal creatinine clearance. We measured the renal uptake of (99m)Tc-DMSA 3 h after its injection in 13 patients with Dent disease or Lowe syndrome, both of which are typical proximal tubular disorders with defective megalin and cubilin-mediated endocytosis. Serial images of three patients were also obtained at 0.5, 1, 2 and 3 h post-injection. The correlations between renal uptake of (99m)Tc-DMSA and creatinine clearance and the degrees of acidemia and tubular proteinuria were then evaluated. The renal uptake of (99m)Tc-DMSA was markedly decreased in all patients, and the decreased uptake was detected in all serial images. In contrast, bladder radioactivity was higher than normal in all of the serial images when compared to renal radioactivity. Additionally, the uptake of (99m)Tc-DMSA was inversely proportional to the amount of urine beta(2)-microglobulin. These results strongly suggest that DMSA is filtered in the glomeruli and subsequently undergoes megalin- and cubilin-mediated endocytosis in the proximal tubules.

  2. Insight into the structure and stability of Tc and Re DMSA complexes: A computational study.

    PubMed

    Hernández-Valdés, Daniel; Blanco-González, Alejandro; García-Fleitas, Ariel; Rodríguez-Riera, Zalua; Meola, Giuseppe; Alberto, Roger; Jáuregui-Haza, Ulises

    2017-01-01

    Meso-2,3-dimercaptosuccinic acid (DMSA) is used in nuclear medicine as ligand for preparation of diagnostic and therapy radiopharmaceuticals. DMSA has been the subject of numerous investigations during the past three decades and new and significant information of the chemistry and pharmacology of DMSA complexes have emerged. In comparison to other ligands, the structure of some DMSA complexes is unclear up today. The structures and applications of DMSA complexes are strictly dependent on the chemical conditions of their preparation, especially pH and components ratio. A computational study of M-DMSA (M=Tc, Re) complexes has been performed using density functional theory. Different isomers for M(V) and M(III) complexes were studied. The pH influence over ligand structures was taken into account and the solvent effect was evaluated using an implicit solvation model. The fully optimized complex syn-endo Re((V))-DMSA shows a geometry similar to the X-ray data and was used to validate the methodology. Moreover, new alternative structures for the renal agent (99m)Tc((III))-DMSA were proposed and computationally studied. For two complex structures, a larger stability respect to that proposed in the literature was obtained. Furthermore, Tc((V))-DMSA complexes are more stable than Tc((III))-DMSA proposed structures. In general, Re complexes are more stable than the corresponding Tc ones.

  3. Biokinetics and dosimetric studies about 99mTc(V)-DMSA distribution.

    PubMed

    Correia, M B L; Magnata, S S L P; Silva, I M S; Catanho, M T J A; Lima, F F

    2010-05-10

    Research for radiodiagnostic agents should considerate biological critical parameters which will give own contribution on the absorbed dose. The dimercaptosuccinic acid (DMSA) labeled with (99m)Tc(V) is a radiopharmaceutical which has well established role in medullar thyroid carcinoma and has been proposed in evaluation of bone metastasis. This work studied the biokinetics and dosimetry of (99m)Tc(V)-DMSA by animal model. The (99m)Tc(V)-DMSA was prepared from a (III)DMSA kit alkalized. Mice (n=5) received (99m)Tc(V)DMSA i.v., they were sacrificed (30 min, 1h, 5h and 12h), the organs excised and the activities measured by a gamma counter. The results were evaluated based on %activity/g and the absorbed dose was estimated (MIRDOSE 3.0 program) by extrapolation of data from animal to human scale. The results showed the majority of organs reached the top uptake at 30 min, the greatest kidney uptake was (4.81 +/- 1.38)% activity/g, while the bone presented its highest uptake at 1h (5.49+/- 0.47)% activity/g, after 1h all the organs had activity exponential decrease. The biokinetic profile of (99m)Tc(V)-DMSA was well established, allowing quantifying of residence time, and the radiation dose estimates were made for this agent. About the absorbed dose, the preliminary results showed higher value to bone, being the soft tissue dose relatively low.

  4. Mistargeting of SH3TC2 away from the recycling endosome causes Charcot-Marie-Tooth disease type 4C.

    PubMed

    Roberts, Rhys C; Peden, Andrew A; Buss, Folma; Bright, Nicholas A; Latouche, Morwena; Reilly, Mary M; Kendrick-Jones, John; Luzio, J Paul

    2010-03-15

    Mutations in the functionally uncharacterized protein SH3TC2 are associated with the severe hereditary peripheral neuropathy, Charcot-Marie-Tooth disease type 4C (CMT4C). Similarly, to other proteins mutated in CMT, a role for SH3TC2 in endocytic membrane traffic has been previously proposed. However, recent descriptions of the intracellular localization of SH3TC2 are conflicting. Furthermore, no clear functional pathogenic mechanisms have so far been proposed to explain why both nonsense and missense mutations in SH3TC2 lead to similar clinical phenotypes. Here, we describe our intracellular localization studies, supported by biochemical and functional data, using wild-type and mutant SH3TC2. We show that wild-type SH3TC2 targets to the intracellular recycling endosome by associating with the small GTPase, Rab11, which is known to regulate the recycling of internalized membrane and receptors back to the plasma membrane. Furthermore, we demonstrate that SH3TC2 interacts preferentially with the GTP-bound form of Rab11, identifying SH3TC2 as a novel Rab11 effector. Of clinical pathological relevance, all SH3TC2 constructs harbouring disease-causing mutations are shown to be unable to associate with Rab11 with consequent loss of recycling endosome localization. Moreover, we show that wild-type SH3TC2, but not mutant SH3TC2, influences transferrin receptor dynamics, consistent with a functional role on the endocytic recycling pathway. Our data therefore implicate mistargeting of SH3TC2 away from the recycling endosome as the fundamental molecular defect that leads to CMT4C.

  5. Tc1 mouse model of trisomy-21 dissociates properties of short- and long-term recognition memory.

    PubMed

    Hall, Jessica H; Wiseman, Frances K; Fisher, Elizabeth M C; Tybulewicz, Victor L J; Harwood, John L; Good, Mark A

    2016-04-01

    The present study examined memory function in Tc1 mice, a transchromosomic model of Down syndrome (DS). Tc1 mice demonstrated an unusual delay-dependent deficit in recognition memory. More specifically, Tc1 mice showed intact immediate (30sec), impaired short-term (10-min) and intact long-term (24-h) memory for objects. A similar pattern was observed for olfactory stimuli, confirming the generality of the pattern across sensory modalities. The specificity of the behavioural deficits in Tc1 mice was confirmed using APP overexpressing mice that showed the opposite pattern of object memory deficits. In contrast to object memory, Tc1 mice showed no deficit in either immediate or long-term memory for object-in-place information. Similarly, Tc1 mice showed no deficit in short-term memory for object-location information. The latter result indicates that Tc1 mice were able to detect and react to spatial novelty at the same delay interval that was sensitive to an object novelty recognition impairment. These results demonstrate (1) that novelty detection per se and (2) the encoding of visuo-spatial information was not disrupted in adult Tc1 mice. The authors conclude that the task specific nature of the short-term recognition memory deficit suggests that the trisomy of genes on human chromosome 21 in Tc1 mice impacts on (perirhinal) cortical systems supporting short-term object and olfactory recognition memory.

  6. Development of a 99Mo/99mTc generator using alumina microspheres for industrial radiotracer applications.

    PubMed

    Dash, Ashutosh; Chakravarty, Rubel; Ram, Ramu; Pillai, K T; Yadav, Yugandhara Y; Wagh, D N; Verma, Rakesh; Biswas, Sujoy; Venkatesh, Meera

    2012-01-01

    A chromatographic (99)Mo/(99m)Tc generator for industrial applications has been developed using alumina microspheres synthesized through sol-gel process to obtain (99m)Tc in both aqueous and non-aqueous media. The sorbent was mesoporous, mechanically strong and possessed high surface area. (99m)Tc could be eluted from generator system using either acetone or 0.9% NaCl solution with appreciably high yields and high radiochemical as well as radionuclidic purity. The facile, versatile generator provides an efficient way to access (99m)Tc at industrial sites for radiotracer applications.

  7. Adoptive Transfer of Tumor-Specific Tc17 Effector T Cells Controls the Growth of B16 Melanoma in Mice

    PubMed Central

    de la Luz Garcia-Hernandez, Maria; Hamada, Hiromasa; Reome, Joyce B.; Misra, Sara K.; Tighe, Michael P.; Dutton, Richard W.

    2010-01-01

    In vitro generated OVA-specific IL-17–producing CD8 T effector cells (Tc17) from OT-1 mice, adoptively transferred into B16-OVA tumor-bearing mice, controlled tumor growth in early and late stage melanoma. IL-17, TNF, and IFN-γ from the Tc17 effectors all played a role in an enhanced recruitment of T cells, neutrophils, and macrophages to the tumor. In addition, Tc17 cells and recently recruited, activated neutrophils produced further chemokines, including CCL3, CCL4, CCL5, CXCL9, and CXCL10, responsible for the attraction of type 1 lymphocytes (Th1 and Tc1) and additional neutrophils. Neutrophils were rapidly attracted to the tumor site by an IL-17 dependent mechanism, but at later stages the induction of the chemokine CXCL2 by Tc17-derived TNF and IFN-γ contributed to sustain neutrophil recruitment. Approximately 10–50 times as many Tc17 effectors were required compared with Tc1 effectors to exert the same level of control over tumor growth. The recruitment of neutrophils was more prominent when Tc17 rather than Tc1 were used to control tumor and depletion of neutrophils resulted in a diminished capacity to control tumor growth. PMID:20237297

  8. Technetium-99 MAS NMR spectroscopy of a cationic framework material that traps TcO4- ions

    SciTech Connect

    Yu, P.; Wang, Shuao; Alekseev, Evgeny V.; Depmeier, Wulf; Albrecht-Schmitt, Thomas E.; Phillips, Brian L.; Casey, William H.

    2010-07-15

    99Tc magic-angle spinning (MAS) NMR spectra show that TcO4- ions, which are generated by nuclear fission and can contaminate the environment, can be trapped within the channels and cavities of a cationic framework material (see picture). These spectra are among the first 99Tc MAS NMR spectra reported to date, and show that the TcO4- ions can be efficiently removed from simulated nuclear waste solutions.

  9. Tc1 mouse model of trisomy-21 dissociates properties of short- and long-term recognition memory

    PubMed Central

    Hall, Jessica H.; Wiseman, Frances K.; Fisher, Elizabeth M.C.; Tybulewicz, Victor L.J.; Harwood, John L.; Good, Mark A.

    2016-01-01

    The present study examined memory function in Tc1 mice, a transchromosomic model of Down syndrome (DS). Tc1 mice demonstrated an unusual delay-dependent deficit in recognition memory. More specifically, Tc1 mice showed intact immediate (30 sec), impaired short-term (10-min) and intact long-term (24-h) memory for objects. A similar pattern was observed for olfactory stimuli, confirming the generality of the pattern across sensory modalities. The specificity of the behavioural deficits in Tc1 mice was confirmed using APP overexpressing mice that showed the opposite pattern of object memory deficits. In contrast to object memory, Tc1 mice showed no deficit in either immediate or long-term memory for object-in-place information. Similarly, Tc1 mice showed no deficit in short-term memory for object-location information. The latter result indicates that Tc1 mice were able to detect and react to spatial novelty at the same delay interval that was sensitive to an object novelty recognition impairment. These results demonstrate (1) that novelty detection per se and (2) the encoding of visuo-spatial information was not disrupted in adult Tc1 mice. The authors conclude that the task specific nature of the shortterm recognition memory deficit suggests that the trisomy of genes on human chromosome 21 in Tc1 mice impacts on (perirhinal) cortical systems supporting short-term object and olfactory recognition memory. PMID:26868479

  10. Tc-99m-labeled red blood cells for the measurement of red cell mass in newborn infants: concise communication

    SciTech Connect

    Linderkamp, O.; Betke, K.; Fendel, H.; Klemm, J.; Lorenzen, K.; Riegel, K.P.

    1980-07-01

    In vitro and in vivo investigations were performed to examine the binding of Tc-99m to neonatal red blood cells (RBC). Labeling efficiency was about 90%, and unbound Tc-99m less than 3% after one washing, in premature and full-term newborns and in children. Thus presence of high percentages of fetal hemoglobin (Hb F) did not influence the labeling of RBCs with Tc-99m. RBCs of 11 newborns were hemolysed and the distribution of Tc-99m on RBC components was analyzed. Although Hb F percentage averaged (60.0 +- 8.10)% (s.d.), only (11.9 +- 3.7)% of Tc-99m was bound by Hb F, whereas (45.0 +- 6.1)% was associated with Hb A. RBC membranes bound (13.7 +- 4.3)% and (29.3 +- 4.0)% were found unbound in hemolysates. These results indicate that Tc-99m preferentially binds to beta chains. In vivo equilibration of Tc-99m RBCs and of albumin labeled with Evans blue was investigated in five newborn infants. Tc-99m RBCs were stable in each case during the first hour after injection. Elution of Tc-99m from RBCs was (3.4 +- 1.5)% per h. Body-to-venous hematocrit ratio averaged 0.86 +- 0.03.

  11. Size Control of (99m)Tc-tin Colloid Using PVP and Buffer Solution for Sentinel Lymph Node Detection.

    PubMed

    Kim, Eun-Mi; Lim, Seok Tae; Sohn, Myung-Hee; Jeong, Hwan-Jeong

    2015-06-01

    Colloidal particle size is an important characteristic that allows mapping sentinel nodes in lymphoscintigraphy. This investigation aimed to introduce different ways of making a (99m)Tc-tin colloid with a size of tens of nanometers. All agents, tin fluoride, sodium fluoride, poloxamer-188, and polyvinylpyrrolidone (PVP), were mixed and labeled with (99m)Tc. Either phosphate or sodium bicarbonate buffers were used to adjust the pH levels. When the buffers were added, the size of the colloids increased. However, as the PVP continued to increase, the size of the colloids was controlled to within tens of nanometers. In all samples, phosphate buffer added PVP (30 mg) stabilized tin colloid ((99m)Tc-PPTC-30) and sodium bicarbonate solution added PVP (50 mg) stabilized tin colloid ((99m)Tc-BPTC-50) were chosen for in vitro and in vivo studies. (99m)Tc-BPTC-50 (<20 nm) was primarily located in bone marrow and was then secreted through the kidneys, and (99m)Tc-PPTC-30 (>100 nm) mainly accumulated in the liver. When a rabbit was given a toe injection, the node uptake of (99m)Tc-PPTC-30 decreased over time, while (99m)Tc-BPTC-50 increased. Therefore, (99m)Tc-BPTC-50 could be a good candidate radiopharmaceutical for sentinel node detection. The significance of this study is that nano-sized tin colloid can be made very easily and quickly by PVP.

  12. The kidney: Imaging with Tc-99m mercaptoacetyltriglycine, a technetium-labeled analog of iodohippurate

    SciTech Connect

    Russell, C.D.; Thorstad, B.L.; Stutzman, M.E.; Yester, M.V.; Fowler, D.; Dubovsky, E.V.

    1989-08-01

    A new renal imaging agent, technetium-99m mercaptoacetyltriglycine (MAG3, mertiatide), is currently undergoing clinical trials. Like iodine-131 orthoiodohippurate (OIH)--and unlike all other available agents--it is avidly secreted by the renal tubules. Fifty patients underwent simultaneous renal imaging studies with I-131 OIH and Tc-99m MAG3. The superior physical properties of the Tc-99m label led to better image quality in all cases, largely due to count rates that were 50-fold better. In two patients, lesions were seen with MAG3 that were not visible with OIH. The biological properties of the two agents were found to be so similar that conventional diagnostic criteria for I-131 OIH could be used for Tc-99m MAG3 with only minor modifications.

  13. Evidence for intrinsic superconductivity at Tc1 in PrOs4Sb12

    NASA Astrophysics Data System (ADS)

    Andraka, B.; Pocsy, K.

    2012-04-01

    Superconductivity in PrOs4Sb12 shows unusual sample size dependence. Large good quality crystals exhibit two superconducting transitions at Tc1 (˜1.85 K) and Tc2 (˜1.74 K). The upper temperature transition is manifested by the change of slope in C/T. It is shown that this transition is suppressed when the crystal is polished to a thickness smaller than 50 μm. At the same time the polishing enhances the transition at Tc2. This behavior is independent on whether material studied is removed from the interior or contains the original surface of the as-cast crystal. The effect of sample polishing is similar to that of powdering, which clearly induces a large number of defects.

  14. Preparation of (99m)Tc-C(60)(OH)(x) and its biodistribution studies.

    PubMed

    Qingnuan, Li; yan, Xiu; Xiaodong, Zhang; Ruili, Liu; qieqie, Du; Xiaoguang, Shun; Shaoliang, Chen; Wenxin, Li

    2002-08-01

    The biological behavior of fullerene derivatives shows their considerable potential for medical applications. In order to provide a C(60) derivative for biodistriburtion studies, the (99m)Tc-labeling of C(60)(OH)(x) was optimized. Gamma counting and single photon emission computed tomography (SPECT) were used to assess the biodistribution of the (99m)Tc-labeled compound in mice and rabbits. Biodistribution studies in mice and imaging of rabbits indicated that (99m)Tc-C(60)(OH)(x) was widely distributed in all tissues. A significant percentage of total activity was retained for 48 h, particularly in the kidneys, bone, spleen, and liver. All tissues displayed a slow clearance over 48 h, except for bone, which showed slightly increasing localization within 24 h.

  15. Assessment of Using 99Mo and 99mTc Isotopes in Kuwait Medical Sector

    PubMed Central

    Ali, Naser

    2016-01-01

    Abstract The Ministry of Health (MOH) in the state of Kuwait currently depends on importing the radioisotope molybdenum (Mo) in its isotopic form (99Mo) to fulfill its demands. The present study was conducted on all nuclear medicine departments in the state of Kuwait. Daily, weekly, and monthly data were analyzed to statistically determine the current and future demands for the isotope 99mTc. This analysis was performed by collecting and analyzing data on MOH consumption of 99mTc for different diagnostic applications. The overall results indicate a partial decrease of 1.012% in the overall total demand for 99mTc up to the year 2018 for the state of Kuwait. PMID:26910031

  16. Mitochondrial Cardiomyopathy with a Unique 99mTc-MIBI/123I-BMIPP Mismatch Pattern

    PubMed Central

    Tashiro, Ryosuke; Onoue, Noriko; Rikimaru, Hiroya; Tsukita, Kenichi; Fujita, Hiroshi; Yamaguchi, Nobuhiro; Ishizuka, Takeshi; Suzuki, Yasushi; Suzuki, Hiroyoshi; Shinozaki, Tsuyoshi

    2017-01-01

    A 42-year-old man was referred to our hospital due to chest pain, diabetes mellitus, and sensorineural hearing loss. Transthoracic echocardiography revealed diffuse left ventricular hypokinesis. He was diagnosed with mitochondrial disease and a c.A3243G mutation was identified in his mitochondrial DNA. This case of mitochondrial cardiomyopathy demonstrated a low uptake of 123I-BMIPP, while the uptake of 99mTc-MIBI was preserved. In contrast, previous reports have noted the increased uptake of123I-BMIPP and the decreased uptake of 99mTc-MIBI. This is the first study to show this unique 99mTc-MIBI/123I-BMIPP mismatch pattern. We also discuss the relationships among the cardiac scintigraphy, cardiac magnetic resonance imaging, and histopathology findings. PMID:28154277

  17. Hydroxyapatite Based 99Mo - 99Tc and 188W - 188Re Generator Systems

    SciTech Connect

    Knapp Jr, Russ F; Monroy-Guzman, F.; Badillo, V. E.; Cosgrove, John M; De La Torre, J.A. Flores

    2006-01-01

    This paper describes studies evaluating the use of hydroxyapatite as the adsorbent material for both {sup 99}Mo-{sup 99m}Tc and {sup 188}W-{sup 188}Re generator systems. Hydroxyapatite is an insoluble solid with anion exchange properties. A study of the sorption behaviour of {sup 99}Mo, {sup 99m}Tc, {sup 188}W and {sup 188}Re on hydroxyapatite in NaCl medium was evaluated by batch experiments. The results demonstrated that while {sup 99}Mo, {sup 99m}Tc and {sup 188}Re are not adsorbed by the hydroxyapatite in NaCl solutions (Kd <5), {sup 188}W is strongly adsorbed (Kd >500). On the basis of these measurements, hydroxyapatite {sup 188}W-{sup 188}Re generator systems were then constructed and eluted in NaCl solutions. The hydroxyapatite based {sup 188}W-{sup 188}Re generator performances are presented.

  18. Abdominal and hepatic uptake of /sup 99m/Tc-pyrophosphate in neonatal necrotizing enterocolitis

    SciTech Connect

    Caride, V.J.; Touloukian, R.J.; Ablow, R.C.; Lange, R.C.; Matthews, T.

    1981-04-01

    Abdominal /sup 99m/Tc-pyrophosphate (/sup 99m/Tc-PYP) scans were obtained in 15 neonates: 12 with neonatal necrotizing enterocolitis (NEC), two with osteomyelitis, and one with myocarditis. Ten of the babies with NEC had at least one positive scan; of these 10 studies, seven (Group A) showed both diffuse abdominal uptake and localized hepatic activity, two (Group B) showed abdominal uptake and questionable hepatic uptake, and one (Group C) demonstrated diffuse abdominal uptake only. The other two babies with NEC had normal scans (Group D). All NEC patients had normal scans. A patient with myocarditis had hepatic uptake of /sup 99m/Tc-PYP while the abdominal scan in the two infants with osteomyelitis was normal. These preliminary observations suggest that further study of a relationship between abdominal scan findings and the course of NEC is warranted.

  19. Tc45, a dimorphic Trypanosoma cruzi immunogen with variable chromosomal localization, is calreticulin.

    PubMed

    Aguillón, J C; Ferreira, L; Pérez, C; Colombo, A; Molina, M C; Wallace, A; Solari, A; Carvallo, P; Galindo, M; Galanti, N; Orn, A; Billetta, R; Ferreira, A

    2000-01-01

    We demonstrate that Tc45, a polypeptide described as an immunogenetically restricted Trypanosoma cruzi antigen in mice, is calreticulin, a dimorphic molecule encoded by genes with variable chromosomal distribution. Previously we showed that IgG from A.SW (H2s) mice immunized with T. cruzi trypomastigotes or epimastigotes and sera from infected humans recognize Tc45, a 45 kD parasite polypeptide. Herein we describe the cloning, sequencing, and expression of the Tc45 gene. A 98% homology in the deduced amino acid sequence was found with a T. cruzi calreticulin-like molecule and 41% with Leishmania donovani and human calreticulin. In the T. cruzi CL Brener clone and in the Tulahuén strain, the gene is located in two and four chromosomes, respectively. Calreticulin was detected in several T. cruzi clones, in the Tulahuén strain, and in T. rangeli, displaying alternative 43 and 46 kD forms.

  20. The research on tool wear of high speed milling titanium alloy TC4

    NASA Astrophysics Data System (ADS)

    Shi, Hongliang; Wang, Zhichao; Ren, Huanhuan; Yuan, Haoteng

    2017-01-01

    In this paper, carbide cutting tools with physical vapor deposition (PVD) coating was used to high speed milling α+β phase TC4 titanium alloy. The PVD tool was used to study the process of milling TC4 titanium alloy tool wear patterns and wear mechanisms. The results showed that the PVD coating surface wear was small after cutter blade. The cutting life was long, it was suitable for processing of titanium alloy TC4, the wear of rake face was mainly adhesion wear and oxidation wear, the flank face was mainly boundary wear. That was because the adhesion wear of the rake face and the boundary wear of the flank face had a weakening effect on the cutting edge , which made the micro crack blade of the main cutting edge.

  1. Diagnosis of hepatobiliary disease in infants and children with Tc-99m-diethyl-IDA imaging

    SciTech Connect

    Ohi, R.; Klingensmith, W.C.; Lilly, J.R.

    1981-07-01

    Thirteen infants and children from 42 days to 14 years old with hepatobiliary disease underwent Tc-99m-diethyl-IDA hepatobiliary imaging. Five patients had biliary atresia, four had biliary hypoplasia, two had neonatal hepatitis, and there were single examples of alpha-1-antitrypsin deficiency and congenital hepatic fibrosis. Tc-99m-diethyl-IDA imaging accurately differentiated biliary atresia (complete bile duct obstruction) from other forms of childhood hepatobiliary disease by demonstrating no intestinal radioactivity in the former and the presence of intestinal radioactivity in the latter. In addition, two of four patients with biliary hypoplasia had nonhomogeneous parenchymal transit, and the one patient with congenital hepatic fibrosis showed possible intrahepatic cysts. In conclusion, these preliminary data indicate that Tc-99m-diethyl-IDA provides information not previously available with I-131-rose bengal; this information is likely to be useful in the noninvasive evaluation of childhood hepatobiliary disease.

  2. SPECT measurements with /sup 99m/Tc-HM-PAO in focal epilepsy

    SciTech Connect

    Ryding, E.; Rosen, I.; Elmqvist, D.; Ingvar, D.H.

    1988-12-01

    The ability of SPECT measurements with (/sup 99m/Tc)-HM-PAO (Ceretec) to find the location of the epileptic focus was studied in patients under consideration for neurosurgical treatment for therapy-resistant focal epilepsy. The location of low (/sup 99m/Tc)-HM-PAO uptake regions found at interictal measurements, and of high (/sup 99m/Tc)-HM-PAO uptake regions found at ictal measurements, was compared to the findings of extensive ictal and interictal EEG examinations, and to the results of CT and MRT. While EEG revealed focal epileptic activity in all of the 14 patients, SPECT showed regional abnormalities in 13 (93%). CT and MRT showed abnormal findings in 30%.

  3. Search for high-Tc conventional superconductivity at megabar pressures in the lithium-sulfur system

    NASA Astrophysics Data System (ADS)

    Kokail, Christian; Heil, Christoph; Boeri, Lilia

    2016-08-01

    Motivated by the recent report of superconductivity above 200 K in ultra-dense hydrogen sulfide, we search for high-TC conventional superconductivity in the phase diagram of the binary Li-S system, using ab initio methods for crystal structure prediction and linear response calculations for the electron-phonon coupling. We find that at pressures higher than 20 GPa, several new compositions, besides the known Li2S , are stabilized; many exhibit electride-like interstitial charge localization observed in other alkali-metal compounds. Of all predicted phases, only an fcc phase of Li3S , metastable before 640 GPa, exhibits a sizable TC, in contrast to what is observed in sulfur and phosphorus hydrides, where several stoichiometries lead to high TC. We attribute this difference to 2 s -2 p hybridization and avoided core overlap, and predict similar behavior for other alkali-metal compounds.

  4. Photo-production of (99)Mo/(99m)Tc with electron linear accelerator beam.

    PubMed

    Avagyan, R; Avetisyan, A; Kerobyan, I; Dallakyan, R

    2014-09-01

    We report on the development of a relatively new method for the production of (99)Mo/(99m)Tc. The method involves the irradiation of natural molybdenum using high-intensity bremsstrahlung photons from the electron beam of the LUE50 linear electron accelerator located at the Yerevan Physics Institute (YerPhi). The production method has been developed and shown to be successful. The linear electron accelerator at YerPhi was upgraded to allow for significant increases of the beam intensity and spatial density. The LUE50 was also instrumented by a remote control system for ease of operation. We have developed and tested the (99m)Tc extraction from the irradiation of natural MoO3. This paper reports on the optimal conditions of our method of (99)Mo production. We show the success of this method with the production and separation of the first usable amounts of (99m)Tc.

  5. 99mTc-HMPAO perfusion SPECT/CT in the diagnosis of brain death.

    PubMed

    Derlin, Thorsten; Weiberg, Desiree

    2016-01-01

    This report describes a case of brain death (BD) evaluated by 99mTc-hexamethylpropylene amine oxime (HMPAO) single photon emission tomography/computed tomography (SPECT/CT). A 16-year-old boy with a history of rapid unexpected brain herniation due to pilocytic astrocytoma underwent 99mTc-HMPAO SPECT/CT for evaluation of brain death in the context of organ donation. Flow images demonstrated lack of blood flow to the brain, and delayed images showed absence of demonstrable radionuclide activity within the brain. SPECT/CT confirmed absence of tracer accumulation, and was deemed helpful for evaluation of the brain stem. 99mTc-HMPAO SPECT/CT is a valuable tool enabling imaging-based confirmation of BD.

  6. Abdominal masses in children: multiorgan imaging with /sup 99m/Tc methylene diphosphonate

    SciTech Connect

    Siddiqui, A.R.; Cohen, M.; Moran, D.P.

    1982-07-01

    /sup 99m/Tc methylene diphosphonate (/sup 99m/Tc MDP) imaging was performed in 29 consecutive children with abdominal masses. Dynamic images of the inferior vena cava were obtained by injecting the radiotracer in the feet. Serial renal images were obtained for the next 30 min. Routine bone imaging was performed at about 3 hr. The radionuclide studies of the inferior vena cava accurately diagnosed total obstruction and displacement to the left but not partial obstruction and displacement to the right. The abnormalities on early renal imaging included displacement (14), distortion (seven), obstruction (eight), and nonvisualization (one). All patients with Wilms tumor (eight) had either nonvisualized or distorted renal parenchyma. Patients with neuroblastoma (17) and other tumors (four) had displacement and obstruction. Soft-tissue accumulation of /sup 99m/Tc MDP was noted in two Wilms tumors and 12 neuroblastomas.

  7. Scintigraphy with 99mTc(V)-DMSA in monitoring patients with inflammatory bowel disease.

    PubMed

    Javadi, Hamid; Amiriani, Taghi; Mirkarimi, HoneySadat; Besharat, Sima; Semnani, Shahriar; Abedi, Jamshid; Seyedabadi, Mohammad; Assadi, Majid

    2013-01-01

    The clinical significance of pentavalent technetium-99m dimercaptosuccinic acid (99mTc(V)-DMSA) scintigraphy in diagnosing inflammatory bowel disease (IBD) has not yet been fully elucidated. The aim of this prospective paper was to study the above. This study included 54 patients, 22 females and 32 males (mean age: 36.68±11.49; range: 18-63 years) with IBD who came to our clinics for follow-up and were examined clinically by colonoscopy and 99mTc(V)-DMSA scintigraphy. On the follow-up studies, five patients (9.25%) relapsed, and 49 (90.74%) remained at a steady condition. There was a good correlation between the scintigraphic results and the clinical and colonoscopy data of the patients (P<0.05). In conclusion, our results indicated that 99mTc(V)DMSA scintigraphy can be complementary to colonoscopy for the diagnostic evaluation of IBD.

  8. Debye temperature, thermal expansion, and heat capacity of TcC up to 100 GPa

    SciTech Connect

    Song, T.; Ma, Q.; Tian, J.H.; Liu, X.B.; Ouyang, Y.H.; Zhang, C.L.; Su, W.F.

    2015-01-15

    Highlights: • A number of thermodynamic properties of rocksalt TcC are investigated for the first time. • The quasi-harmonic Debye model is applied to take into account the thermal effect. • The pressure and temperature up to about 100 GPa and 3000 K, respectively. - Abstract: Debye temperature, thermal expansion coefficient, and heat capacity of ideal stoichiometric TcC in the rocksalt structure have been studied systematically by using ab initio plane-wave pseudopotential density functional theory method within the generalized gradient approximation. Through the quasi-harmonic Debye model, in which the phononic effects are considered, the dependences of Debye temperature, thermal expansion coefficient, constant-volume heat capacity, and constant-pressure heat capacity on pressure and temperature are successfully predicted. All the thermodynamic properties of TcC with rocksalt phase have been predicted in the entire temperature range from 300 to 3000 K and pressure up to 100 GPa.

  9. Sequence analyses and chromosomal distribution of the Tc1/Mariner element in Parodontidae fish (Teleostei: Characiformes).

    PubMed

    Schemberger, Michelle Orane; Nogaroto, Viviane; Almeida, Mara Cristina; Artoni, Roberto Ferreira; Valente, Guilherme Targino; Martins, Cesar; Moreira-Filho, Orlando; Cestari, Marta Margarete; Vicari, Marcelo Ricardo

    2016-11-30

    Transposable elements are able to move along eukaryotic genomes. They are divided into two classes according to their transposition intermediate: RNA (class I or retrotransposons) or DNA (class II or DNA transposons). Most of these sequences are inactive or non-autonomous in eukaryotic genomes. Inactivate transposons can accumulate mutations at neutral rates until losing their molecular identity. They may either be eliminated from the genome or take on different molecular functions. Transposable elements may also participate in the differentiation of sex chromosomes. Therefore, the structural variations and nucleotide similarity of Tc1/Mariner sequences were analyzed along with their potential participation in the differentiation processes of sex chromosomes in the genomes of Parodontidae fish. All Parodontidae species presented non-autonomous copies of Tc1/Mariner with structural variation, different levels of deterioration (genetic distance), and variations in insertion and deletion patterns. The physical mapping of Tc1/Mariner on chromosomes revealed dispersed signals in euchromatins, with small accumulations in terminal regions and in the sex chromosomes. The gene dosage ratios indicated copy number variations of Tc1/Mariner among the genomes and high transposase open reading frame deterioration in Parodon hilarii and Parodon pongoensis genomes. This transposon presented transcriptional activity in gonads, but there was no significant difference between sexes. This may indicate non-functional protein expression or may correspond to DNA binding proteins derived from Tc1/Mariner. Thus, our results show Tc1/Mariner inactivation along with a diversity in Parodontidae genomes and its participation in the differentiation of the W sex chromosome.

  10. Potential Ways to Address Shortage Situations of (99)Mo/(99m)Tc.

    PubMed

    Filzen, Leah M; Ellingson, Lacey R; Paulsen, Andrew M; Hung, Joseph C

    2017-03-01

    (99m)Tc, the most common radioisotope used in nuclear medicine, is produced in a nuclear reactor from the decay of (99)Mo. There are only a few aging nuclear reactors around the world that produce (99)Mo, and one of the major contributors, the National Research Universal (Canada), ceased production on October 31, 2016. The National Research Universal produced approximately 40% of the world's (99)Mo supply, so with its shut down, shortages of (99)Mo/(99m)Tc are expected. Methods: Nuclear pharmacies and nuclear medicine departments throughout the United States were contacted and asked to provide their strategies for coping with a shortage of (99)Mo/(99m)Tc. Each of these strategies was evaluated on the basis of its effectiveness for conserving (99m)Tc while still meeting the needs of the patients. Results: From the responses, the following 6 categories of strategies, in order of importance, were compiled: contractual agreements with commercial nuclear pharmacies, alternative imaging protocols, changes in imaging schedules, software use, generator management, and reduction of ordered doses or elimination of backup doses. Conclusion: The supply chain of (99)Mo/(99m)Tc is quite fragile; therefore, being aware of the most appropriate coping strategies is crucial. It is essential to build a strong collaboration between the nuclear pharmacy and nuclear medicine department during a shortage situation. With both nuclear medicine departments and nuclear pharmacies implementing viable strategies, such as the ones proposed, the amount of (99m)Tc available during a shortage situation can be maximized.

  11. A novel approach to infection imaging using a synthetic Tc-99m-labeled leukotactic peptide

    SciTech Connect

    Som, P.; Oster, Z.H.; Sharma, S. ||

    1996-05-01

    RMT1, a synthetic peptide binding to PMN and macrophage receptors was labeled with Tc-99m and investigated as a potential imaging agent for abscess and inflammation. Experimental abscesses were induced in rabbits and dogs by turpentine and E.coli injection. After injection of Tc-99m-RMT1 two and twelve day old abscesses were visualized within 20 min. In initial studies, a dose of 30 {mu}g of peptide/3 mCi was used. This amount was subsequently reduced to 1.5 {mu}g peptide with same amount of Tc-99m yielding similar imaging results. Technetium-99m-IgG and Tc-99m-MAG-3 were used as positive and negative controls, respectively. After injection of IgG abscesses were visualized but activity in blood was always higher than in abscess. When using Tc-99m RMT1 rapid abscess visualization and faster blood clearance was observed. The accumulation of RMT1 was monophasic, i.e., following the initial visualization, activity continued to build up continuously for 1{1/2} hr. Tc-99m-MAG3 accumulated initially in abscess, but activity washed out. In dogs, RMT1 blood clearance showed three components: a fast component with t{1/2}=1.9 min, 73%, intermediate t{1/2}=22 min, 24.5% and slow component, t{1/2}=115, 9.5% with 3 hours cumulative urine excretion of 40-51%. RMT1 appears to be more advantageous than currently available methods because of rapidity of imaging, simpler preparation before injection and will probably be less expensive and time consuming compared to labeled WBC. These results indicate that clinical experiments are warranted.

  12. 99Tc in seawater in the West Spitsbergen Current and adjacent areas.

    PubMed

    Gerland, Sebastian; Lind, Bjørn; Dowdall, Mark; Karcher, M; Kolstad, Anne Kathrine

    2003-01-01

    99Tc levels were measured in seawater samples collected between 2000 and 2002 in the West Spitsbergen Current (WSC) and along the western coast of Svalbard or Spitzbergen and compared with available oceanographic 3-D modelling results for the late 1990s. Additional data from related regions are also presented in order to support the data interpretation. The seawater in the Arctic fjord Kongsfjorden on the western coast of Svalbard is influenced by the WSC, as shown by the 99Tc levels in surface water. By means of the WSC, 99Tc reaches the Eastern Fram Strait, where one branch of the WSC turns west into the East Greenland Current (EGC), and another branch continues northwards into the Arctic Ocean. Surface seawater collected in the central part of the WSC during a cruise on board the R/V "Polarstern" in the summer of 2000, showed higher levels of (99)Tc than samples measured in Kongsfjorden in the spring of 2000. However, all levels measured in surface water are of the same order of magnitude. Data from sampling of deeper water in the WSC and EGC provide information pertaining to the lateral distribution of 99Tc. In all vertical profiling surveys (conducted in spring and summer), the highest levels of 99Tc were found in surface water. Comparison with oceanographic 3-D modelling indicates both significant seasonal variations in the lateral stratification of the WSC and variations with depth over shorter vertical distances. This information can be applied in sampling strategies, environmental monitoring, long-range transport of pollutants and physical oceanography.

  13. Tc(VII) Reduction Kinetics by Titanomagnetite (Fe3-xTixO4) Nanoparticles

    SciTech Connect

    Liu, Juan; Pearce, Carolyn I.; Qafoku, Odeta; Arenholz, Elke; Heald, Steve M.; Rosso, Kevin M.

    2012-09-01

    Technetium contamination remains a major environmental problem at nuclear reprocessing sites, such as at the Hanford nuclear reservation, Washington, U.S.A. Here we investigate the heterogeneous reduction of the highly soluble pertechnetate anion [Tc(VII)O4-] to sparingly soluble Tc(IV)-bearing solids by a novel and well-characterized set of mixed-valent titanium-doped magnetite nanoparticles, structurally and chemically analogous to titanomagnetites naturally present in Hanford sediments. Titanomagnetite (Fe3 xTixO4) nanoparticles (10-12 nm) with varying Ti content (0 ≤ x ≤ 0.53) were synthesized in aqueous suspension. Reaction with 10 and 30 μM Tc(VII) solution yielded fast exponentially decaying reduction kinetics with rates that increased with increasing solid-state Fe(II)/Fe(III) ratio in the nanoparticles, a characteristic systematically controlled by the Ti-content. Nanoparticles before and after reduction experiments and surface-associated products of Tc(VII) reduction were characterized using transmission electron microscopy (TEM), X-ray absorption nearedge spectroscopy (XANES), extended X-ray absorption fine structure spectroscopy (EXAFS), micro Xray diffraction (μ-XRD), X-ray absorption (XA) and X-ray magnetic circular dichroism (XMCD). A mechanistic reaction model was developed involving reduction of Tc(VII) to form Tc(IV)/Fe(III) solids by structural Fe(II) enriched at the nanoparticle surface, a reactive Fe(II) pool that during reaction is resupplied and sustained by outward migration of Fe(II) from the particle interior with concurrent inward migration of charge-balancing cationic vacancies in a ratio of 3:1. The reaction process was quantitatively linked to mass and electron balanced changes in the Fe3-xTixO4 nanoparticles, and the accessibility of structural Fe(II) from these phases was determined.

  14. VCD spectroscopic and molecular dynamics analysis of the Trp-cage miniprotein TC5b.

    PubMed

    Copps, Jeffrey; Murphy, Richard F; Lovas, Sándor

    2007-01-01

    TC5b is a 20 residue polypeptide notable for its compact tertiary structure, a rarity for a short peptide. This structure is due to the "Trp-cage" motif, an association of aromatic, Pro, and Gly residues. The structure of TC5b has been fully characterized by NMR and electronic circular dichroism (ECD) studies, but has never been studied with vibrational circular dichroism (VCD) spectroscopy, which may reveal finer structure. In this study, we examine the VCD spectra of TC5b to characterize the spectroscopic signature of the peptide and its comprising structural elements. TC5b exhibited a negative-positive-negative triplet which is associated with alpha-helical structure in deuterated solvents but also signs of a polyproline II (PPII) helix in the amide I' region. Detection of this element was complicated by the aforementioned triplet form, as well as by an upfrequency shift in PPII helical elements due to the use of the deuterated organic solvents DMSO-d(6) and TFE-d(1). Nevertheless, while ECD spectra showed only alpha-helical structure for TC5b, VCD spectroscopy revealed a more complex structure which was in agreement with NMR results. VCD spectroscopy also showed a rapid conformational change of the peptide at temperatures above 35 degrees C in D(2)O and in aqueous solvent with greater than 75% DMSO-d(6) content. Molecular dynamics (MD) simulations to investigate this latter effect of DMSO-d(6) on TC5b were conducted in DMSO and 50% (v/v) DMSO in H(2)O. In DMSO unfolding of the peptide was rapid while in 50% (v/v) DMSO in H(2)O the unfolding was more gradual.

  15. Preparation of (99m)Tc-isosulfan blue for lymph node localization in rats (99m)Tc-isosulfan blue for lymph node localization.

    PubMed

    İlem-Özdemir, Derya; Yararbas, Ulkem; Zengel, Baha; Ertan, Gökhan; Asikoglu, Makbule

    2016-12-01

    The sentinel lymph node (SLN) is defined as the first regional lymph node to receive lymphatic drainage from a malignant tumor. Therefore, this node is a "sentinel" for second metastatic lymph node stations and for labeling regional tumor spread. For SLN detection, many surgeons preferred a combination of a preoperative injection of radiolabeled colloid and the intraoperative injection of blue dye. Under this combination protocol, nodes are considered to be "sentinel nodes" if they are radioactive and blue. The aim of this study is to develop a new single agent that combines both detection methods. For this purpose Isosulfan Blue (ISB) was radiolabeled by (99m)Tc with high labeling yield and stability. In vivo gamma scintigraphy studies were performed with rats. According to the scintigraphic studies, (99m)Tc-ISB shows rapid and high accumulation in both axillary (ALN) and popliteal lymph node (PLN). After the imaging study, extremity was opened and nodes were scanned for the radioactivity. According to performed study the lymph nodes were clearly seen to become blue and carried compound was sufficient to allow identification with a gamma probe. In conclusion, (99m)Tc-ISB has the potential to facilitate lymphatic mapping and subsequent sentinel node biopsy for solid malignancies such as breast cancer and melanoma.

  16. Trypanosoma cruzi TcI and TcII transmission among wild carnivores, small mammals and dogs in a conservation unit and surrounding areas, Brazil.

    PubMed

    Rocha, Fabiana Lopes; Roque, André Luiz Rodrigues; Arrais, Ricardo Corassa; Santos, Jean Pierre; Lima, Valdirene dos Santos; Xavier, Samanta Cristina das Chagas; Cordeir-Estrela, Pedro; D'Andrea, Paulo Sérgio; Jansen, Ana Maria

    2013-02-01

    Aiming to better understand the ecological aspects of Trypanosoma cruzi transmission cycles, wild carnivores, small mammals and dogs were examined for T. cruzi infection in the Serra da Canastra National Park region, Brazil. Isolates were genotyped using mini-exon gene and PCR-RFLP (1f8 and H3) genomic targets. Trypanosoma cruzi transmission was well established in the area and occurred in both wild and peridomestic environments. Dog seroprevalence was 29·4% (63/214) and TcI and TcII genotypes, besides mixed infections were observed. Only TcI was detected in wild mammals. Marsupials displayed lower relative abundance, but a high prevalence of positive haemocultures (4/22), whereas rodents displayed positive haemocultures (9/113) mainly in the abundant Akodon montensis and Cerradomys subflavus species. The felid Leopardus pardalis was the only carnivore to display positive haemoculture and was captured in the same region where the small mammal prevalence of T. cruzi infection was high. Two canid species, Chrysocyon brachyurus and Cerdocyon thous, were serologically positive for T. cruzi infection (4/8 and 8/39, respectively), probably related to their capacity to exploit different ecological niches. Herein, dog infection not only signals T. cruzi transmission but also the genotypes present. Distinct transmission strategies of the T. cruzi genotypes are discussed.

  17. Vesicocolic fistula detected by (99m)Tc-MAG3 renogram.

    PubMed

    Mannelli, Lorenzo; Monti, Serena; Bastawrous, Sarah; Lomabardo, Ivano; Behnia, Fatemeh

    2015-01-01

    A 55-year-old man presented with 60-lb weight loss in 6 months. An abdominal CT demonstrated a large mass in the pelvis arising from the sigmoid colon and invading the urinary bladder. His elevated serum creatinine (1.25 mg/dL) triggered a request for a Tc-MAG3. Tc-MAG3 renogram demonstrated communication of the urinary bladder with the descending colon but no evidence of obstruction to drainage from the kidneys to the bladder. A retrograde cystogram confirmed a vesicocolic fistula. After multiple rounds of chemotherapy, the patient died 7 months later.

  18. Intraperitoneal urine leak after prostatectomy confirmed by 99mTc-MAG3 renogram.

    PubMed

    Pogatchnik, Brian; Monti, Serena; Lewis, David H; Heinrich, Demetra A; Mannelli, Lorenzo

    2014-08-01

    A 67-year-old patient presented with abdominal pain and distension 2 days after robotic radical prostatectomy for prostate carcinoma. He became anuric, and his serum creatinine level doubled, making IV contrast contraindicated. Abdominal CT without contrast demonstrated hypodense fluid in the peritoneum. Tc-MAG3 renogram detected extravasation of radiotracer from the bladder. Follow-up retrograde cystogram revealed a posterior anastomotic leak. The patient underwent uneventful surgical repair and made a full recovery. This case demonstrated that Tc-MAG3 can prove leak from the urinary tract, particularly helpful in the setting of poor renal function and contraindication to IV contrast.

  19. Validation of alternative methods of preparing 99mTc-MAG3.

    PubMed

    Seetharaman, Shankar; Sosabowski, Michael H; Ballinger, James R

    2007-11-01

    Parameters in the preparation of 99mTc-mertiatide (99mTc-MAG3) were investigated to determine the importance of total activity, activity concentration, boiling time, and delay before boiling for the radiochemical purity (RCP) and stability of the product. Satisfactory RCP results (>90%) were obtained over a range of concentrations including a dilute preparation for paediatric use. RCP was not affected by the time between the addition of pertechnetate and boiling, but low RCP (<60%) resulted when the kit was boiled for less than 10 min.

  20. An incidental detection of aortic aneurysm on Tc-99m MAG3 renal scintigraphy.

    PubMed

    Sadic, Murat; Demirel, Koray; Koca, Gökhan; Atilgan, Hasan Ikbal; Korkmaz, Meliha

    2013-01-01

    A 71-year-old man with newly diagnosed hypertension was referred for Technetium-99m mercaptoacetyltriglycine (Tc-99m MAG3) renal scintigraphy to evaluate the recent onset of impairment in renal functions. Dynamic imaging revealed activity flow which was suspicious for aortic aneurysm (AA) with a concurrent decrease in left renal blood flow. CT angiography of the thoracoabdominal aorta confirmed that this area corresponded to AA. The purpose of this report was to present the first case of incidental detection of AA on Tc-99m MAG3 scintigraphy and highlight the importance of correlative imaging for the diagnosis of abnormal radioactivity accumulation in the region of vascular structures.

  1. Tc1 clonal T cell expansion during chronic graft-versus-host disease-associated hypereosinophilia.

    PubMed

    Clave, Emmanuel; Xhaard, Aliénor; Douay, Corrine; Adès, Lionel; Cayuela, Jean Michel; Peffault de Latour, Régis; Robin, Marie; Toubert, Antoine; Socié, Gérard

    2014-05-01

    Although hypereosinophilia (HE) associated with chronic graft-versus-host disease (GVHD) has long been recognized, biological data on this phenomenon are scarce. Here we compare patients with chronic GVHD with HE together with a clonal T cell expansion and control patients with acute or chronic GVHD but without HE. These clonal expansions share a CD8(+) TC1 phenotype rather than a CD4(+) Th2 profile. In contrast to the drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome, these allogeneic CD8(+) clones do not recognize the epitopes of herpesviruses. Furthermore, these TC1 clones do not produce IL-17 as described in the DRESS syndrome.

  2. Trypanosoma cruzi: TcRAB7 protein is localized at the Golgi apparatus in epimastigotes.

    PubMed

    Araripe, Júlia R; Cunha e Silva, Narcisa L; Leal, Simone T; de Souza, Wanderley; Rondinelli, Edson

    2004-08-20

    In mammalian cells, the Rab7 protein is a key element of late endocytic membrane traffic. Several results suggest that it is involved in the transport from early to late endosome or from late endosome to lysosome. We have previously characterized a Rab7 gene homologue (TcRAB7) in Trypanosoma cruzi. Now, using an affinity-purified antibody specific to TcRAB7 protein we have determined that it is localized at the Golgi apparatus of the parasite. Our results indicate that the T. cruzi Rab7 homologue may function in a different route than its counterparts in mammalian cells.

  3. [Differential expression of DTSsa4 Tc1-like transposons in closely related populations of Baikal ciscoes].

    PubMed

    Bychenko, O S; Sukhanova, L V; Azhikina, T L; Sverdlov, E D

    2009-01-01

    Two representatives of Baikal ciscoes - lake cisco and omul - diverged from a common ancestor as recently as 10-20 thousand years ago. We have found an increasing expression level of DTSsa4 Tc1-like DNA transposons in cisco and omul brains. The mapping of the sequences of these transposons from Salmo salar and Danio rerio genomes has shown that in some cases, these transposons are located in the 5' and 3' regions, as well as in the promoter regions of various genes. Probably, Tc1-like transposons affect the activity of neighboring genes, providing the adaptive divergence of the cisco population.

  4. Failure to diagnose cardiac treatment rejection with Tc99m-PYP images

    SciTech Connect

    McKillop, J.H.; McDougall, I.R.; Goris, M.L.; Mason, J.W.; Reitz, B.A.

    1981-08-01

    The possibility of diagnosing transplant rejection using Tc-99m-PYP imaging was examined in 12 cardiac transplant recipients. Two patients were studied on two occasions. The presence or absence of active rejection was established by endomyocardial biopsy. The intensity and pattern of myocardial uptake of the tracer did not differ significantly in the two patients studied at the time of rejection compared to the remainder. It is concluded that a single Tc-99m-PYP study cannot be used to diagnose cardiac transplant rejection.

  5. Renal accumulation of /sup 99m/Tc-DMSA in the artificially perfused isolated rat kidney

    SciTech Connect

    Goldraich, N.P.; Alvarenga, A.R.; Goldraich, I.H.; Ramos, O.L.; Sigulem, D.

    1985-12-01

    In order to investigate aspects of the renal handling of /sup 99m/Tc-DMSA, 68 isolated rat kidneys were artificially perfused. The experimental groups were: Group 1 (no. = 32)-oxygenated filtering kidneys; Group 2 (no. = 29)-oxygenated non-filtering kidneys; Group 3 (no. = 7)-anaerobic non-filtering kidneys. The authors conclude that the /sup 99m/Tc-DMSA complex is strongly bound to albumin, is not filtered and is removed from perfusion fluid through the renal peritubular capillary route and that this occurs by an active process which depends upon aerobic metabolism. This process has a high capacity and is not inhibited by probenecid.

  6. Extrarenal abnormalities in Tc-99m-DTPA renal blood flow studies

    SciTech Connect

    Shih, W.J.; Domstad, P.A.; DeLand, F.H.

    1985-01-01

    The authors observed extrarenal abnormalities during renal flow scintigraphy and retrospectively reviewed 90 patient studies to determine the types and frequencies of such abnormal findings. For each routine Tc-99m-DTPA renal flow study, they obtained nine 2-second sequential images, which included the heart, abdominal aorta, spleen and kidneys. Eighty abnormalities, observed in 62 patients, were divided into three categories: aortic, 37 cases; splenic, 40 cases; and miscellaneous, 3 cases. Other correlative studies including Tc-99m sulfur colloid-spleen scintigraphy, ultrasonography (US), CT, aortography, and surgical and/or autopsy findings were available for corroboration in 56 of 80 lesions.

  7. Neurofibromas: location by scanning with Tc-99m DTPA. Work in progress

    SciTech Connect

    Mandell, G.A.; Herrick, W.C.; Harcke, H.T.; Sharkey, C.; Brooks, K.M.; MacEwen, G.D.

    1985-12-01

    The accumulation of technetium-99m diethylenetriamine pentaacetic acid (Tc-99m DTPA) in benign soft-tissue neurofibromatosis tumors is reported. In a series of 16 patients with clinical stigmata of neurofibromatosis, 28 sites of abnormal soft-tissue localization of the isotope observed scintigraphically were documented to be sites of soft-tissue tumor by clinical and/or radiographic (predominantly computed tomographic) correlations. The smallest lesion detected was a 1.5-cm subcutaneous neurofibroma. Normal physiologic nonrenal distribution of the Tc-99m DTPA was established by scintigraphic imaging of a control population.

  8. Choledochal cyst with bile duct dilatation: sonography and /sup 99m/Tc IDA cholescintigraphy

    SciTech Connect

    Han, B.K.; Babcock, D.S.; Gelfand, M.H.

    1981-06-01

    Three cases of choledochal cyst associated with intrahepatic biliary dilatation are presented. Findings on sonography included a large cystic mass in the porta hepatis separate from the gallbladder; a dilated common hepatic or common bile duct entering directly into the cyst; and smaller cystic masses of dilated central intrahepatic ducts. All three patients underwent operation with intraoperative cholangiography. Two patients had /sup 99m/Tc IDA cholescintigraphy which confirmed the diagnosis of choledochal cyst by demonstrating filling of the cyst with stasis and delayed intestinal activity. The accurate preoperative diagnosis of choledochal cyst, made by sonography combined with /sup 99m/Tc IDA cholescintigraphy, obviated invasive studies.

  9. A computerized compact module for separation of (99m)Tc-radionuclide from molybdenum.

    PubMed

    Chattopadhyay, Sankha; Barua, Luna; De, Anirban; Saha Das, Sujata; Kuniyil, Remashan; Bhaskar, Partha; Pal, Sasanka Shekhar; Sarkar, Sishir Kumar; Das, Malay Kanti

    2012-11-01

    An automated closed cycle module for the separation and recovery of various isotopes, radioactive or non-radioactive, using solvent extraction and column chromatography techniques, and in particular, for separation and recovery of (99m)Tc from low-medium specific activity (99)Mo, is described. The module may also be applicable for separation of (99m)Tc produced in a cyclotron. The module is safe and reliable to avoid human interference and hazards posed by handling of radioactive and hazardous chemicals. The entire system of automation includes a user-friendly PC based graphical user interface (GUI) that actually supervises the process via an embedded system based electronic controller.

  10. Chiral symmetry breaking and confinement effects on dilepton and photon production around Tc

    NASA Astrophysics Data System (ADS)

    Satow, Daisuke; Weise, Wolfram

    2015-09-01

    Production rates of dileptons and photons from the quark-gluon (QGP) phase are calculated taking into account effects of confinement and spontaneous chiral symmetry breaking (χ SB ) not far from the transition temperature Tc. We find that the production rates of dileptons with large momenta and of photons originating from the QGP around Tc are suppressed by the χ SB effect. We also discuss to what extent information about details of the chiral transition, such as its characteristic temperature range and the steepness of the crossover, are reflected in these quantities.

  11. Mechanical resonance characteristics of a high-{Tc} superconducting levitation system

    SciTech Connect

    Sugiura, Toshihiko; Fujimori, Hideki

    1996-05-01

    This research deals with dynamic response of a permanent magnet freely levitated above an excited high-{Tc} superconductor. Evaluation of dynamic characteristics is required in mechanical design of high-{Tc} superconducting levitation systems. Their dynamics is coupled with Type-II superconducting phenomena. By a numerical approach based on some macroscopic models they evaluate mechanical resonance characteristics of a superconducting levitation system. Numerical results show some nonlinear properties and effect of the flux flow in Type-II superconductor, which are observed in experiments or predicted by analyses.

  12. Numerical analyses of levitation force and flux creep on high [Tc] superconductor

    SciTech Connect

    Tsuchimoto, M.; Kojima, T.; Takeuchi, H.; Honma, T. . Dept. of Electrical Engineering)

    1993-11-01

    Large levitation force and a stable equilibrium are obtained with a permanent magnet and a bulk high [Tc] superconductor (HTSC). Evaluation of the levitation force is important for many applications, such as magnetically levitated vehicles, magnetic bearing, flywheel and linear drive. Levitation force between a permanent magnet and a high [Tc] superconductor is examined by using two numerical methods. The levitation force to vertical direction is calculated by using the critical state model. Stiffness of restoring force to horizontal direction is calculated by using a frozen-in field model. Numerical solutions agree well with experimental results. Dynamic properties of the levitation force are also analyzed by combining the two methods.

  13. Increased 99mTc-MDP Activity in a Partially Calcified Malignant Mediastinal Teratoma.

    PubMed

    Li, Wei; Zhang, Linqi; Zhang, Rusen

    2016-02-01

    A 41-year-old woman presented with cough and shortness of breath for 3 weeks. Chest x-ray and CT showed a large, partially calcified soft tissue mass adjacent to the right side of the heart. Whole-body bone was acquired to evaluate possible metastases, which showed abnormal accumulation of Tc-MDP in the right chest. Further SPECT/CT imaging that demonstrated intense Tc-MDP activity was mainly in the calcification portion of mass. Histopathological examination from biopsy specimen of the lesion was consistent with malignant teratoma.

  14. Unusual Tc-99m MDP and I-123 MIBG images in focal pyelonephritis

    SciTech Connect

    Jacobs, A.; Lenoir, P.; Delree, M.; Ramet, J.; Piepsz, A. )

    1990-11-01

    A 6-year-old boy presented with an inflammatory syndrome. Because Tc-99m MDP bone scintigraphy revealed increased tracer uptake at the upper pole of the right kidney, further studies were oriented towards a diagnosis of renal or adrenal pathology. I-123 metaiodobenzylguanidine (MIBG) accumulated at the site of the abnormal MDP uptake. The diagnosis of neuroblastoma or allied disorder was excluded on the basis of other investigations and further evaluation, suggesting that the MIBG uptake was a false-positive. Findings on clinical imaging, laboratory findings, Tc-99m DMSA imaging, sonography, and CT scanning were highly suggestive of acute focal pyelonephritis.

  15. Synthesis and Biological Evaluation of a New Nitroimidazole-99mTc-Complex for Imaging of Hypoxia in Mice Model

    PubMed Central

    Zhang, Qing; Zhang, Qing; Guan, Yanxing; Liu, Shaozheng; Chen, Qingjie; Li, Xiangmin

    2016-01-01

    Background This study was specifically designed to develop a new 99mTc compound with 3-amino-4-[2-(2-methyl-5-nitro-1H-imidazol)-ethylamino]-4-oxo-butyrate (5-ntm-asp) and to verify whether this compound is feasible to be a radiopharmaceutical for hypoxic tumors. Material/Methods Metronidazole derivative 5-ntm-asp was synthesized and then radio-labeled by Na [99mTcO4], forming 99mTc-5-ntm-asp. Another two complexes of 99mTc-2- and 99mTc-5-nitroimidazole-iminodiacetic acid (99mTc-2-ntm-IDA and 99mTc-5-ntm-IDA) were also synthesized based on previous studies. Physicochemical properties (stability, lipophilicity, protein binding) of the compounds were compared, and we also assessed the accumulation status of the compounds within A549 cells under both hypoxic and aerobic conditions. Distribution of the complex was also studied in vivo using BALB/c nude mice that were injected with A549 cells. Results Compared with 99mTc-2-ntm-IDA and 99mTc-5-ntm-IDA, 99mTc-5-ntm-asp was more stable in both phosphate-buffered saline (PBS) buffer and human plasma (P<0.05). Besides that, 99mTc-5-ntm-asp offered lower lipophilicity and protein-binding rate than the two complexes (P<0.05). During assessment of hypoxic uptake status and high hypoxic/aerobic ratio in mice injected with A549 cells, 99mTc-5-ntm-asp exhibited a more favorable profile than 9mTc-2-ntm-IDA and 99mTc-5-ntm-IDA, including uptake ratio of tumor/blood and uptake ratio of tumor/muscle. Conclusions With overall consideration of physicochemical properties and biological uptake behavior, it is feasible to use 99mTc-5-ntm-asp as an imaging agent for tumor hypoxia. PMID:27752036

  16. Quantitative simultaneous 111In/99mTc SPECT-CT of osteomyelitis

    PubMed Central

    Cervo, Morgan; Gerbaudo, Victor H.; Park, Mi-Ae; Moore, Stephen C.

    2013-01-01

    Purpose: A well-established approach for diagnostic imaging of osteomyelitis (OM), a bone infection, is simultaneous SPECT-CT of 99mTc sulfur colloid (SC) and 111In white blood cells (WBC). This method provides essentially perfect spatial registration of the tracers within anatomic sites of interest. Currently, diagnosis is based purely on a visual assessment—where relative discordance between 99mTc and 111In uptake in bone, i.e., high 111In and low 99mTc, suggests OM. To achieve more quantitative images, noise, scatter, and crosstalk between radionuclides must be addressed through reconstruction. Here the authors compare their Monte Carlo-based joint OSEM (MC-JOSEM) algorithm, which reconstructs both radionuclides simultaneously, to a more conventional triple-energy window-based reconstruction (TEW-OSEM), and to iterative reconstruction with no compensation for scatter (NC-OSEM). Methods: The authors created numerical phantoms of the foot and torso. Multiple bone-infection sites were modeled using high-count Monte Carlo simulation. Counts per voxel were then scaled to values appropriate for 111In WBC and 99mTc SC imaging. Ten independent noisy projection image sets were generated by drawing random Poisson deviates from these very low-noise images. Data were reconstructed using the two iterative scatter-compensation methods, TEW-OSEM and MC-JOSEM, as well as the uncorrected method (NC-OSEM). Mean counts in volumes of interest (VOIs) were used to evaluate the bias and precision of each method. Data were also acquired using a phantom, approximately the size of an adult ankle, consisting of regions representing infected and normal bone marrow, within a bone-like attenuator and surrounding soft tissue; each compartment contained a mixture of 111In and 99mTc. Low-noise data were acquired during multiple short scans over 29 h on a Siemens Symbia T6 SPECT-CT with medium-energy collimators. Pure 99mTc and 111In projection datasets were derived by fitting the acquired

  17. The Study of 99mTc-Aluminum Oxide Using for Sentinel Lymph Nodes Detection in Experiment

    NASA Astrophysics Data System (ADS)

    Medvedeva, A. A.; Sinilkin, I. G.; Zelchan, R. V.; Chernov, V. I.; Lyapunov, A. Yu.; Bragina, O. D.; Varlamova, N. V.; Skuridin, V. S.; Dergilev, A. P.

    2016-06-01

    The purpose of the study was a comparative research of the possibility of using the radiopharmaceuticals 99mTc-Al2O3 and 99mTc-Nanocis for visualizing sentinel lymph nodes in the experiment. Measurement of the sizes of 99mTc-Al2O3 and 99mTc-Nanocis colloidal particles was performed in seven series of radiopharmaceuticals. Pharmacokinetics of 99mTc-Al2O3 and 99mTc-Nanocis was researched on 50 white male rats. The possibility of the use of 99mTc-Al2O3 and 99mTc-Nanocis for lymphoscintigraphy was studied in the experiments on 12 white male rats. Average dynamic diameter of the sol particle was 52-77 nm for 99mTc-Al2O3 and 16.7-24.5 nm for 99mTc-Nanocis. Radiopharmaceuticals accumulated in the inguinal lymph node - at 1 hour after administration the average uptake of 99mTc-Al2O3 was 8.6% in it and the accumulation of 99mTc-Nanocis was significantly lower - 1,8% (p <0,05). In all study point average uptake of 99mTc-Al2O3 in the lymph node was significantly higher 99mTc-Nanocis accumulation. The results dynamic scintigraphic studies in rats showed that 99mTc-Al2O3 and 99mTc-Nanocis actively accumulated into the lymphatic system. By using 99mTc-Al2O3 inguinal lymph node was determined in 5 minutes after injection and clearly visualize in all the animals in the 15th minute, when the accumulation became more than 1% of the administered dose. Further observation indicated that the 99mTc-Al2O3 accumulation reaches a plateau in a lymph node (average 10.5%) for 2 hour study and then its accumulation remains practically at the same level, slightly increasing to 12% at 24 hours. In the case of 99mTc-Nanocis inguinal lymph node visualized in all animals for 15 minutes when it was accumulated on the average 1.03% of the administered dose. Plateau of 99mTc-Nanocis accumulation in the lymph node (average 2.05%) occurred at 2 hour of the study and remained almost on the same level (in average 2.3%) to 24 hours. Thus, the experimental study of a new domestic radiopharmaceutical showed

  18. Lung uptake on Tc-99m albumin colloid liver spleen scan and on Ga-67 scan in angiotropic lymphoma

    SciTech Connect

    Kacki, M.H.; Joyce, J.M.; Coupal, J.J.; Ryo, U.Y. )

    1990-03-01

    Lung uptake of Tc-99m sulfur colloid has been reported in various hepatic and extrahepatic diseases, and lung uptake of gallium-67 may occur in patients with various interstitial lung disease without radiographic abnormality. This may be the first case of Tc-99m albumin colloid and Ga-67 lung uptake in a patient with angiotropic lymphoma of the liver, spleen, and uterus.

  19. Assessment of RELAP5/MOD3 Version 7 based on the BETHSY Test 6.2 TC

    SciTech Connect

    Choi, C.J.; Roth, P.A.; Schultz, R.R.

    1992-08-01

    This document provides a discussion of the BETHSY test 6.2 TC which was conducted to investigate thermal hydraulic phenomena during a 5% cold leg SBLOCA and to provide high quality data for advanced thermal-hydraulic code assessment. BETHSY test 6.2 TC was analyzed using RELAP5/MOD3 version 7o.

  20. Choledochal cyst complicated by acute cholecystitis and bypass obstruction: diagnostic role of Tc-99m-HIDA cholescintigraphy

    SciTech Connect

    Weissmann, H.S.; Gold, M.; Goldstein, R.D.; Sugarman, L.A.; Freeman, L.M.

    1981-09-01

    An unusual case of malignant degeneration of a choledochal cyst is presented. The presence of acute cholecystitis with the cystic duct originating from the cyst as well as the subsequent obstruction of the cyst-jejunal surgical anastomosis was readily detected with Tc-99m-dimethyl-iminodiacetic (Tc-99m-HIDA) cholescintigraphy.

  1. Targeted disruption of TC-PTP in the proliferative compartment augments STAT3 and AKT signaling and skin tumor development

    PubMed Central

    Lee, Hyunseung; Kim, Mihwa; Baek, Minwoo; Morales, Liza D.; Jang, Ik-Soon; Slaga, Thomas J.; DiGiovanni, John; Kim, Dae Joon

    2017-01-01

    Tyrosine phosphorylation is a vital mechanism that contributes to skin carcinogenesis. It is regulated by the counter-activities of protein tyrosine kinases (PTKs) and protein tyrosine phosphatases (PTPs). Here, we report the critical role of T-cell protein tyrosine phosphatase (TC-PTP), encoded by Ptpn2, in chemically-induced skin carcinogenesis via the negative regulation of STAT3 and AKT signaling. Using epidermal specific TC-PTP knockout (K14Cre.Ptpn2fl/fl) mice, we demonstrate loss of TC-PTP led to a desensitization to tumor initiator 7,12-dimethylbenz[a]anthracene (DMBA)-induced apoptosis both in vivo epidermis and in vitro keratinocytes. TC-PTP deficiency also resulted in a significant increase in epidermal thickness and hyperproliferation following exposure to the tumor promoter, 12-O-tetradecanoylphorbol-13-acetate (TPA). Western blot analysis showed that both phosphorylated STAT3 and phosphorylated AKT expressions were significantly increased in epidermis of TC-PTP-deficient mice compared to control mice following TPA treatment. Inhibition of STAT3 or AKT reversed the effects of TC-PTP deficiency on apoptosis and proliferation. Finally, TC-PTP knockout mice showed a shortened latency of tumorigenesis and significantly increased numbers of tumors during two-stage skin carcinogenesis. Our findings reveal that TC-PTP has potential as a novel target for the prevention of skin cancer through its role in the regulation of STAT3 and AKT signaling. PMID:28322331

  2. Gambol and Tc1 are two distinct families of DD34E transposons: analysis of the Anopheles gambiae genome expands the diversity of the IS630-Tc1-mariner superfamily.

    PubMed

    Coy, M R; Tu, Z

    2005-10-01

    Tc1 is a family of DNA transposons found in diverse organisms including vertebrates, invertebrates and fungi. Tc1 belongs to the IS630-Tc1-mariner superfamily, which is characterized by common 'TA' target site and conserved D(Asp)DE(Glu) or DDD catalytic triad. All functional Tc1-like transposons contain a transposase with a DD34E catalytic triad. We conducted a systematic analysis of DD34E transposons in the African malaria mosquito, Anopheles gambiae, using a reiterative and exhaustive search program. In addition to previously described Tc1-like elements, we uncovered 26 new DD34E transposons including a novel family that we named gambol. Designation of family status to gambol is based on phylogenetic analyses of transposase sequences that showed gambol and Tc1 transposons as distinct clades that were separated by mariner and other families of the IS630-Tc1-mariner superfamily. The distinction between Tc1 and gambol is also consistent with the unique TIRs in gambol elements and the presence of a 'W[I/L/V]DEDC' signature near their N-termini. This signature is predicted as part of the 'RED' domain, a component of the 'PAI' and 'RED' DNA binding domains in Tc1 and possibly mariner. Although gambol appears to be related to a few DD34E transposons from cyanobacteria and fungi, no gambol has been reported in any other insects or animals thus far. Several gambol and Tc1 elements have intact ORFs and different genomic copies with high sequence identity, which suggests that they may have been recently active.

  3. Further Evidence That the CFTR Variant c.2620-6T>C Is Benign.

    PubMed

    Wallerstein, Violet I; Wallerstein, Robert

    2017-01-01

    The c.2620-6T>C variant in the CFTR gene is a rare variant about which little is known. We present an asymptomatic adult who has this variant as well as the well described delta F508 pathogenic variant in transpresentation. This patient provides additional evidence that this is a benign polymorphism.

  4. 99mTc-bioorthogonal click chemistry reagent for in vivo pretargeted imaging

    PubMed Central

    García, María Fernanda; Zhang, Xiuli; Shah, Manankumar; Newton-Northup, Jessica; Cabral, Pablo; Cerecetto, Hugo; Quinn, Thomas

    2016-01-01

    Metal-free click chemistry has become an important tool for pretargeted approaches in the molecular imaging field. The application of bioorthogonal click chemistry between a pretargeted trans-cyclooctene (TCO) derivatized monoclonal antibody (mAb) and a 99mTc-modified 1,2,4,5-tetrazine for tumor imaging was examined in vitro and in vivo. The HYNIC tetrazine compound was synthesized and structurally characterized, confirming its identity. Radiolabeling studies demonstrated that the HYNIC tetrazine was labeled with 99mTc at an efficiency of >95% and was radiochemically stable. 99mTc-HYNIC tetrazine reacted with the TCO-CC49 mAb in vitro demonstrating its selective reactivity. In vivo biodistribution studies revealed non-specific liver and GI uptake due to the hydrophobic property of the compound, however pretargeted SPECT imaging studies demonstrated tumor visualization confirming the success of the cycloaddition reaction in vivo. These results demonstrated the potential of 99mTc- HYNIC-tetrazine for tumor imaging with pretargeted mAbs. PMID:26875936

  5. Further Evidence That the CFTR Variant c.2620-6T>C Is Benign

    PubMed Central

    Wallerstein, Violet I.

    2017-01-01

    The c.2620-6T>C variant in the CFTR gene is a rare variant about which little is known. We present an asymptomatic adult who has this variant as well as the well described delta F508 pathogenic variant in transpresentation. This patient provides additional evidence that this is a benign polymorphism. PMID:28163942

  6. Predictive value of XPG rs2296147T>C polymorphism on clinical outcomes of cancer patients

    PubMed Central

    Wang, Yuhan; Han, Yingying; Weng, Qiang; Yuan, Zhengrong

    2016-01-01

    The Xeroderma pigmentosum complementation group G (XPG) rs2296147T>C polymorphism is suspected to associate with the clinical outcomes of cancer patients. However, the results are inconsistent. This meta-analysis aimed to evaluate the reliable predictive value of XPG rs2296147T>C polymorphism on clinical outcomes of cancer patients. A total of 11 eligible studies were enrolled in this meta-analysis. Our results indicated that the cancer patients with TT and CT genotypes were significantly associated with better respond rates when compared with the CC genotype (TT versus (vs.) CC: odds ratio (OR) = 2.05, 95% confidence intervals (CIs), 1.32-3.20, P = 0.002; TT+CT vs. CC: OR= 1.57, 95% CI, 1.14-2.17, P = 0.005). The TT genotype and/or T allele might be associated with higher survival time for cancer patients than the CC genotype and/or C allele. The cumulative meta-analyses showed an apparent beneficial objective response of TT genotype on cancer patients. In conclusion, this meta-analysis suggests that the XPG rs2296147T>C polymorphism is associated with the clinical outcomes of cancer patients. The XPG rs2296147T>C polymorphism might be a predictive factor of prognosis in cancers patients and contribute to individual treatment in the future. PMID:27588464

  7. Kit for the selective labeling of red blood cells in whole blood with .sup.9 TC

    DOEpatents

    Srivastava, Suresh C.; Babich, John W.; Straub, Rita; Richards, Powell

    1992-01-01

    Disclosed herein are a method and kit for the preparation of .sup.99m Tc labeled red blood cells using whole blood in a closed sterile system containing stannous tin in a form such that it will enter the red blood cells and be available therein for reduction of technetium.

  8. New method for the selective labeling of erythrocytes in whole blood with Tc-99m

    DOEpatents

    Srivastava, S.C.; Babich, J.W.; Straub, R.; Richards, P.

    1984-01-27

    Method and kit are described for the preparation of /sup 99m/Tc labeled red blood cells using whole blood in a closed sterile system containing stannous tin in a form such that it will enter the red blood cells and be available therein for the reduction of technetium.

  9. Excision and transposition activity of Tc1/mariner superfamily transposons in sea urchin embryos.

    PubMed

    Sasakura, Yasunori; Yaguchi, Junko; Yaguchi, Shunsuke; Yajima, Mamiko

    2010-03-01

    Tc1/mariner superfamily transposons are used as transformation vectors in various model organisms. The utility of this transposon family is evidenced by the fact that Tc1/mariner transposons have loose host specificity. However, the activity of these transposons has been observed in only a few organisms, and a recent study in the ascidian Ciona intestinalis suggests that not all Tc1/ mariner transposons show loose host specificity. To understand host specificity, we used sea urchins, since they have a long history as materials of embryology and developmental biology. Transposon techniques have not been reported in this organism, despite the likelihood that these techniques would open up many experimental possibilities. Here we tested the activity of three Tc1/ mariner transposons (Minos, Sleeping Beauty, and Frog Prince) in the sea urchin Hemicentrotus pulcherrimus. Minos has both excision and transposition activity in H. pulcherrimus embryos, whereas no excision activity was detected for Sleeping Beauty or Frog Prince. This study suggests that Minos is active in a broad range of non-host organisms and can be used as a transformation tool in sea urchin embryos.

  10. Liquid scintillation counting methodology for 99Tc analysis. A remedy for radiopharmaceutical waste

    SciTech Connect

    Khan, Mumtaz; Um, Wooyong

    2015-08-13

    This paper presents a new approach for liquid scintillation counting (LSC) analysis of single-radionuclide samples containing appreciable organic or inorganic quench. This work offers better analytical results than existing LSC methods for technetium-99 (99gTc) analysis with significant savings in analysis cost and time. The method was developed to quantify 99gTc in environmental liquid and urine samples using LSC. Method efficiency was measured in the presence of 1.9 to 11,900 ppm total dissolved solids. The quench curve was proved to be effective in the case of spiked 99gTc activity calculation for deionized water, tap water, groundwater, seawater, and urine samples. Counting efficiency was found to be 91.66% for Ultima Gold LLT (ULG-LLT) and Ultima Gold (ULG). Relative error in spiked 99gTc samples was ±3.98% in ULG and ULG-LLT cocktails. Minimum detectable activity was determined to be 25.3 mBq and 22.7 mBq for ULG-LLT and ULG cocktails, respectively. A pre-concentration factor of 1000 was achieved at 100°C for 100% chemical recovery.

  11. Effects of concurrent drug therapy on technetium /sup 99m/Tc gluceptate biodistribution

    SciTech Connect

    Hinkle, G.H.; Basmadjian, G.P.; Peek, C.; Barker, K.K.; Ice, R.D.

    1982-11-01

    Drug interactions with /sup 99m/Tc gluceptate resulting in altered biodistribution were studied using chart review and animal tests. Charts of nine patients who had abnormal gallbladder uptake of technetium /sup 99m/Tc gluceptate during a two-year period were reviewed to obtain data such as concurrent drug therapy, primary diagnosis, and laboratory values. Adult New Zealand white rabbits were then used for testing the biodistribution of technetium /sup 99m/Tc gluceptate when administered concurrently with possibly interacting drugs identified in the chart review--penicillamine, penicillin G potassium, penicillin V potassium, acetaminophen, and trimethoprim-sulfamethoxazole. Chart review revealed no conclusive patterns of altered biodistribution associated with other factors. The data did suggest the possibility that the five drugs listed above might cause increased hepatobiliary clearance of the radiopharmaceutical. Animal tests showed that i.v. penicillamine caused substantial distribution of radioactivity into the gallbladder and small bowel. Minimally increased gallbladder radioactivity occurred when oral acetaminophen and trimethoprim-sulfamethoxazole were administered concurrently. Oral and i.v. penicillins did not increase gallbladder activity. Penicillamine may cause substantial alteration of the biodistribution of technetium /sup 99m/Tc gluceptate.

  12. Role of 99mTc-ECD SPECT in the Management of Children with Craniosynostosis

    PubMed Central

    Barik, Mayadhar; Bajpai, Minu; Das, Rashmi Ranajn; Malhotra, Arun; Panda, Shasanka Shekhar; Sahoo, Manas Kumar; Dwivedi, Sadanand

    2014-01-01

    Purpose of the Report. There is a paucity of data on correlation of various imaging modalities with clinical findings in craniosynostosis. Moreover, no study has specifically reported the role of 99mTc-ECD SPECT in a large number of subjects with craniosynostosis. Materials and Methods. We prospectively analyzed a cohort of 85 patients with craniosynostosis from year 2007 to 2012. All patients underwent evaluation with 99mTc-ECD SPECT and the results were correlated with radiological and surgical findings. Results. 99mTc-ECD SPECT revealed regional perfusion abnormalities in the cerebral hemisphere corresponding to the fused sutures preoperatively that disappeared postoperatively in all the cases. Corresponding to this, the mean mental performance quotient (MPQ) increased significantly (P < 0.05) postoperatively only in those children with absent perfusion defect postoperatively. Conclusions. Our study suggests that early surgery and release of craniosynostosis in patients with preoperative perfusion defects (absent on 99mTc-ECD SPECT study) are beneficial, as theylead to improved MPQ after surgery. PMID:24987670

  13. Interplay of 3 d-5 d interactions in high-TC osmium-based double perovskites

    NASA Astrophysics Data System (ADS)

    Taylor, A. E.; Calder, S.; Morrow, R.; Woodward, P. M.; Yan, J. Q.; Winn, B.; Lumsden, M. D.; Christianson, A. D.

    2015-03-01

    In 3d-5d systems the strongly magnetic 3d orbitals and extended 5d orbitals with enhanced spin-orbit coupling lead to a range of high TC magnetic states and novel behavior not present in systems consisting solely of 3d or 5d ions. The two distinct octahedral sites in double perovskites A2 BB 'O6 allow an ordered 3d-5d structure to form, providing a variety of systems to be investigated. Unravelling the interactions controlling these systems, however, is an open challenge. The highest known TC in such a system, 725K, is found in insulator Sr2CrOsO6. This questions the theory for high-TCs in systems such as TC=400K Sr2FeReO6 which relies on half-metallic behavior. To unravel the nature of the interactions in 3d-5d systems, we have studied the series of compounds Sr2 X OsO6. We have utilized elastic and inelastic neutron scattering to probe the spin states in the systems, and therefore test predictions that the magnetic interactions are controlled by a frustrated AFM Heisenberg model. By studying the series, we are able to relate changes in the spin wave spectrum to dramatic changes in the magnetic order from TN = 95 K antiferromagnetism to TC = 725 K ferrimagnetism.

  14. Pharmacologic alterations in Tc-99m binding by red blood cells: concise communication

    SciTech Connect

    Lee, H.B.; Wexler, J.P.; Scharf, S.C.; Blaufox, M.D.

    1983-05-01

    The effect of two antihypertensive agents (captopril and prazosin) and of digoxin on the efficiency of Tc-99m binding to RBCs was evaluated in the rat. RBCs were labeled with Tc-99m in vivo in six groups of rats: I-normotensive controls Wistar rat (WR), II-prazosin treated WR, III-spontaneously hypertensive rat (SHR), IV-prazosin-treated SHR, V-digoxin-treated WR, and VI-captopril-treated WR. The percentage of intravascular Tc-99m bound to RBC (%T) and the percentage of injected dose remaining intravascular 5 min after injection (%i.v.) were determined. Mean %T was 94.2, 83.8, 94.9, 86.1, 79.7, and 93.3 for groups I-VI respectively. Mean %I.V. was 96.4, 74.6, 94.9, 79.0, 74.4, and 87.4 for groups I-VI respectively. The findings demonstrate a significant reduction of RBC tagging with Tc-99m in rats treated with prazosin and digoxin but not with captopril. The data suggest a potential interference by patient medication with the performance of blood-pool studies.

  15. Benign Brenner tumor of the ovary detected on Tc-99m methylene diphosphonate bone scan

    SciTech Connect

    Renner, J.B.; McCartney, W.H.

    1984-11-01

    Many disease states, including neoplasia, have been detected by bone scanning. Among the neoplastic processes detected by bone imaging agents are ovarian tumors, both benign and malignant. This report is concerned with the visualization of a benign Brenner tumor during routine Tc-99m MDP bone scanning.

  16. Arthrobacter aurescens TC1 Metabolizes Diverse s-Triazine Ring Compounds

    PubMed Central

    Strong, Lisa C.; Rosendahl, Charlotte; Johnson, Gilbert; Sadowsky, Michael J.; Wackett, Lawrence P.

    2002-01-01

    Arthrobacter aurescens strain TC1 was isolated without enrichment by plating atrazine-contaminated soil directly onto atrazine-clearing plates. A. aurescens TC1 grew in liquid medium with atrazine as the sole source of nitrogen, carbon, and energy, consuming up to 3,000 mg of atrazine per liter. A. aurescens TC1 is metabolically diverse and grew on a wider range of s-triazine compounds than any bacterium previously characterized. The 23 s-triazine substrates serving as the sole nitrogen source included the herbicides ametryn, atratone, cyanazine, prometryn, and simazine. Moreover, atrazine substrate analogs containing fluorine, mercaptan, and cyano groups in place of the chlorine substituent were also growth substrates. Analogs containing hydrogen, azido, and amino functionalities in place of chlorine were not growth substrates. A. aurescens TC1 also metabolized compounds containing chlorine plus N-ethyl, N-propyl, N-butyl, N-s-butyl, N-isobutyl, or N-t-butyl substituents on the s-triazine ring. Atrazine was metabolized to alkylamines and cyanuric acid, the latter accumulating stoichiometrically. Ethylamine and isopropylamine each served as the source of carbon and nitrogen for growth. PCR experiments identified genes with high sequence identity to atzB and atzC, but not to atzA, from Pseudomonas sp. strain ADP. PMID:12450818

  17. Tc-99m MDP bone scintigraphy in a case of Touraine-Solente-Gole syndrome

    PubMed Central

    Mudalsha, Ravina; Jacob, MJ; Jora, Charu; Pandit, AG

    2011-01-01

    Pachydermoperiostosis is a form of primary hypertrophic osteoarthropathy, also known as Touraine-Solente-Gole syndrome. It is a rare disease. In this report, we present the case of a 29-year-old man with this rare disorder, having significant findings on Tc-99m methylene diphosphonate bone scan. PMID:21969783

  18. Diversification in the Supply Chain of (99)Mo Ensures a Future for (99m)Tc.

    PubMed

    Cutler, Cathy S; Schwarz, Sally W

    2014-07-01

    The uncertain availability of (99m)Tc has become a concern for nuclear medicine departments across the globe. An issue for the United States is that currently it is dependent on a supply of (99m)Tc (from (99)Mo) that is derived solely by production outside the United States. Since the United States uses half the world's (99)Mo production, the U.S. (99)Mo supply chain would be greatly enhanced if a producer were located within the United States. The fragility of the old (99)Mo supply chain is being addressed as new facilities are constructed and new processes are developed to produce (99)Mo without highly enriched uranium. The conversion to low-enriched uranium is necessary to minimize the potential misuse of highly enriched uranium in the world for nonpeaceful means. New production facilities, new methods for the production of (99)Mo, and a new generator elution system for the supply of (99m)Tc are currently being pursued. The progress made in all these areas will be discussed, as they all highlight the need to embrace diversity to ensure that we have a robust and reliable supply of (99m)Tc in the future.

  19. HIPed Tailored Ceramic Waste Forms for the Immobilization of Cs, Sr and Tc

    SciTech Connect

    Melody L. Carter; Martin W. A. Stewart; Eric R. Vance; Bruce D. Begg; Sam Moricca; Julia Tripp

    2007-09-01

    The Advanced Fuel Cycle Initiative is developing advanced technologies to allow for the safe and economical disposal of waste from nuclear reactors. An important element of this initiative is the separation of key radionuclides . One of the systems being developed to separate key radionuclides is the UREX+1 process. The Tc and Cs/Sr solutions from UREX+1 process will require treatment and solidification for managed storage. This paper illustrates the benefits of HIPed tailored ceramic waste forms, to provide for the immobilization of separated Cs, Sr and Tc. Experimental data are presented for a Cs and Sr-bearing hollandite-rich tailored ceramic prepared with 12 wt% waste (on an oxide basis). Normalized MCC-1 type leach testing at 90oC for 28 days revealed extremely low Cs and Sr release rates of 0.003 and 0.004 g/m2/day respectively. Experimental data on the immobilization of Tc in titanate ceramics containing up to 40wt% TcO2 are also be presented.

  20. (99m)Tc-bioorthogonal click chemistry reagent for in vivo pretargeted imaging.

    PubMed

    García, María Fernanda; Zhang, Xiuli; Shah, Manankumar; Newton-Northup, Jessica; Cabral, Pablo; Cerecetto, Hugo; Quinn, Thomas

    2016-03-15

    Metal-free click chemistry has become an important tool for pretargeted approaches in the molecular imaging field. The application of bioorthogonal click chemistry between a pretargeted trans-cyclooctene (TCO) derivatized monoclonal antibody (mAb) and a (99m)Tc-modified 1,2,4,5-tetrazine for tumor imaging was examined in vitro and in vivo. The HYNIC tetrazine compound was synthesized and structurally characterized, confirming its identity. Radiolabeling studies demonstrated that the HYNIC tetrazine was labeled with (99m)Tc at an efficiency of >95% and was radiochemically stable. (99m)Tc-HYNIC tetrazine reacted with the TCO-CC49 mAb in vitro demonstrating its selective reactivity. In vivo biodistribution studies revealed non-specific liver and GI uptake due to the hydrophobic property of the compound, however pretargeted SPECT imaging studies demonstrated tumor visualization confirming the success of the cycloaddition reaction in vivo. These results demonstrated the potential of (99m)Tc-HYNIC-tetrazine for tumor imaging with pretargeted mAbs.

  1. Problems of development the pilot lead-bismuth target circuit TC-1 for ADS

    SciTech Connect

    Ignatiev, Sviatoslav; Leonchuk, Mikhail; Orlov, Yury; Pankratov, Dmitry; Suvorov, Gennady; Zabudko, Alexey

    2007-07-01

    Available in abstract form only. Full text of publication follows: Main problems on development of pilot molten lead-bismuth target circuit of 1 MW proton beam power (TC-1) as an important part of target-blanket accelerator driven system (ADS) for nuclear waste incineration are analyzed. (authors)

  2. Kit for the selective labeling of red blood cells in whole blood with [sup 99]Tc

    DOEpatents

    Srivastava, S.C.; Babich, J.W.; Straub, R.; Richards, P.

    1992-05-26

    Disclosed herein are a method and kit for the preparation of [sup 99m]Tc labeled red blood cells using whole blood in a closed sterile system containing stannous tin in a form such that it will enter the red blood cells and be available therein for reduction of technetium. No Drawings

  3. Positive curvature of the Hc2-versus-Tc boundaries in layered superconductors

    NASA Technical Reports Server (NTRS)

    Woollam, J. A.; Somoano, R. B.; O'Connor, P.

    1974-01-01

    We have found what we believe to be a universal characteristic of layered superconductors: a positive curvature of the Hc2-versus-Tc boundary. The origins of the effect are believed to be associated with strong anisotropies of the Fermi surface and electron-phonon interaction.

  4. Liquid scintillation counting methodology for (99)Tc analysis: a remedy for radiopharmaceutical waste.

    PubMed

    Khan, Mumtaz; Um, Wooyong

    2015-09-01

    This paper presents a new approach for liquid scintillation counting (LSC) analysis of single-radionuclide samples containing appreciable organic or inorganic quench. This work offers better analytical results than existing LSC methods for technetium-99 ((99g)Tc) analysis with significant savings in analysis cost and time. The method was developed to quantify (99g)Tc in environmental liquid and urine samples using LSC. Method efficiency was measured in the presence of 1.9 to 11 900 ppm total dissolved solids. The resultant quench curve proved to be effective for quantifying spiked (99g)Tc activity in deionized water, tap water, groundwater, seawater, and urine samples. Counting efficiency was found to be 91.66% for Ultima Gold LLT (ULG-LLT) and Ultima Gold (ULG). Relative error in spiked (99g)Tc samples was ±3.98% in ULG and ULG-LLT cocktails. Minimum detectable activity was determined to be 25.3 and 22.7 mBq for ULG-LLT and ULG cocktails, respectively. A preconcentration factor of 1000 was achieved at 100 °C for 100% chemical recovery.

  5. Trypanosoma cruzi strain TcI is associated with chronic Chagas disease in the Brazilian Amazon

    PubMed Central

    2014-01-01

    Background Chagas disease in the Amazon region is considered an emerging anthropozoonosis with a predominance of the discrete typing units (DTUs) TcI and TcIV. These DTUs are responsible for cases of acute disease associated with oral transmission. Chronic disease cases have been detected through serological surveys. However, the mode of transmission could not be determined, or any association of chronic disease with a specific T. cruzi DTU’s. The aim of this study was to characterize Trypanosoma cruzi in patients with chronic Chagas disease in the State of Amazonas, Brazil. Methods Blood culture and xenodiagnosis were performed in 36 patients with positive serology for Chagas disease who participated in a serological survey performed in urban and rural areas of Manaus, Amazonas. DNA samples were extracted from the feces of triatomines used for xenodiagnosis, and the nontranscribed spacer of the mini-exon gene and the mitochondrial gene cytochrome oxidase subunit II (COII) were amplified by PCR and sequenced. Results Blood culture and xenodiagnosis were negative in 100% of samples; however, molecular techniques revealed that in 13 out of 36 (36%) fecal samples from xenodiagnosis, T. cruzi was characterized as the DTU TcI, and different haplotypes were identified within the same DTU. Conclusion The DTU TcI, which is mainly associated with acute cases of Chagas disease in the Amazon region, is also responsible for chronic infection in patients from a region in the State of Amazonas. PMID:24916362

  6. Effect of ketamine, pentobarbital, and morphine on Tc-99m-DISIDA hepatobiliary kinetics

    SciTech Connect

    Durakovic, A.; Dubois, A.

    1985-05-01

    The purpose of this study was to evaluate hapatobiliary kinetics of Tc-99m-DISIDA in dogs after administration of anesthetic sedative or narcotic agents. Four groups of six male Beagle dogs were studied as a non-treated control group and after parenteral administration of ketamine (30 mg/kg IM), pentobarbital (25 mg/kg IV) or morphine (1 mg/kg IV). Each animal was injected with 4 mCi Tc-99m-DISIDA and hepatobiliary scintigraphic studies were obtained using a gamma camera with parallel hole multipurpose collimator and an A/sup 3/ MDS computer. The authors determined; peak activity of Tc-99m-DISIDA in the liver, visualization and peak activity of gallbladder, and intestinal visualization of Tc-99m-DISIDA. Total bilirubin, LDH, SGOT and SGPT were not modified significantly after any drug compared to control. The results showed that two commonly used anesthetics and sedatives (ketamine and pentobarbital) have dramatic and opposite effects on extrahepatic biliary kinetics. Furthermore, ketamine, but not pentobarbital, significantly accelerates intrahepatic biliary kinetics. Finally, as expected, morphine delayed extrahepatic biliary kinetics. Thus, studies of biliary kinetics should be interpreted with caution when measurements are made after administration of anesthetic, sedative or narcotic agents.

  7. Current Outlook for 99mTc Distribution Based on Electron Accelerator Production

    SciTech Connect

    Benjamin L. Nelson; W. David Bence; John R. Snyder

    2007-07-01

    In 1999 a practical example illustrating the economical and reliable production of 99mTc from an accelerator was developed. It included the realistic costs involved in establishing and operating the accelerator facility and the distribution of the 99mTc to regions in Florida. However, the technology was never commercialized. Recent political and economic developments prompted this second look at accelerator produced 99mTc. The practicality of this system in 2007 dollars was established to account for inflation and current demand. The same distribution model and production schedule from the Global ‘99 study were used. Numbers were found using current rates and costs where possible and indexed estimations when necessary. Though several of the costs increased significantly and the sale price remains at approximately 35¢/mCi, the unit cost of 99mTc throughput only increased from 12.8¢/mCi to 15.0¢/mCi or approximately 17.2% from 1999 to 2007 thus continuing to be economically viable. This study provides ground work for creating business development models at additional locations within the U.S.

  8. Incidental detection of a bleeding gastrointestinal stromal tumor on Tc-99m red blood cell scintigraphy.

    PubMed

    Santhosh, Sampath; Bhattacharya, Anish; Gupta, Vikas; Singh, Rajinder; Radotra, Bishan Dass; Mittal, Bhagwant Rai

    2012-10-01

    The role of 99m-technetium labeled red blood cell (RBC) scintigraphy in acute gastro-intestinal bleed is well-established. The authors report a case of a bleeding gastrointestinal stromal tumor (GIST) incidentally discovered on Tc-99m RBC scintigraphy.

  9. Use of 99mTc-doxorubicin scintigraphy in females with breast cancer: a pilot study

    PubMed Central

    Araujo, F I; Proença, F P P; Ferreira, C G; Ventilari, S C; Rosado de Castro, P H; Moreira, R D; Fonseca, L M B; Gutfilen, B

    2015-01-01

    Objective: Doxorubicin (Eurofarma, São Paulo, Brazil) is an antitumour agent widely used in the treatment of breast cancer and can be used for tumour tracking when labelled with a radionuclide. Here, we present the results obtained with technetium-99m (99mTc)-doxorubicin, using the direct method, to evaluate its uptake in breast cancer. Methods: Four females with confirmed breast carcinoma diagnosis and breast image reporting and data system Category 5 on mammography underwent whole-body and thorax single-photon emission CT/CT imaging 1 and 3 h after 99mTc-doxorubicin administration. Results: We observed increased uptake in breast carcinoma lesions and elimination via renal and hepatic pathways. Conclusion: These preliminary results suggest that 99mTc-doxorubicin may be a promising radiopharmaceutical for the evaluation of patients with breast cancer. Further studies are ongoing. Advances in knowledge: To our knowledge, this is the first study to evaluate the use of a directly labelled doxorubicin tracer in humans. 99mTc-doxorubicin could provide information on the response of tumours to doxorubicin. PMID:26111270

  10. Changes in biodistribution of radiopharmaceuticals due to impurities - Tc-99m radiopharmaceuticals

    SciTech Connect

    Yokoyama, A.; Horiuchi, K.

    1981-06-01

    In this review the influence of impurities in RP such as Tc-99m complexes of bleomycin, pyridoxylidene-glutamate, DMSA, phosphate derivatives, and Ga-67 citrate will be further discussed from the point of view of their preparation as a way to understanding the labeling reaction of the useful form of a given RP.

  11. Tc-99m DMSA renal uptake: influence of biochemical and physiologic factors

    SciTech Connect

    Yee, C.A.; Lee, H.B.; Blaufox, M.D.

    1981-12-01

    Thirty-eight female Sprague-Dawley rats were studied to determine the effects of (a) tubular blockade and (b) commonly encountered changes in hydration and acid-base balance, on the urinary excretion and renal localization of Tc-99m dimercaptosuccinic acid (DMSA). Ten additional rats were studied to quantitate the in vivo protein binding of Tc-99m DMSA, and a final group of 12 animals was used to quantitate DMSA distribution in animals with diminished functional renal mass. Both osmotic diuresis and dehydration by water deprivation for 24 hr resulted in a plasma clearance of DMSA slower than in control animals. Acid-base imbalances significantly affected the renal accumulation of DMSA, and acidosis was associated with markedly increased background due to increased liver accumulation. The protein-bound portion of Tc-99m DMSA in the plasma was high, reaching 89% within the first 5 min, and rising very slightly (n.s.) with time. The unbound portion of DMSA had a plasma clearance slightly higher than the GFR. Ablation of large amounts of renal tissue, resulting in significant decreases in GFR, did not significantly affect the renal localization of DMSA in the intact portions of the kidneys. These data demonstrate that commonly encountered changes in acid-base balance and hydration will significantly alter the biologic distribution of Tc-99m DMSA. These factors should be controlled when carrying out clinical studies.

  12. 99mTc DMSA renal uptake: influence of biochemical and physiologic factors

    SciTech Connect

    Yee, C.A.; Lee, H.B.; Blaufox, M.D.

    1981-12-01

    Thirty-eight female Sprague-Dawley rats were studied to determine the effects of (a) tubular blockade and (b) commonly encountered changes in hydration and acid-base balance, on the urinary excretion and renal localization of 99mTc dimercaptosuccinic acid (DMSA). Ten additional rats were studied to quantitate the in vivo protein binding of 99mTc DMSA, and a final group of 12 animals was used to quantitate DMSA distribution in animals with diminished functional renal mass. Both osmotic diuresis and dehydration by water deprivation for 24 hr resulted in a plasma clearance of DMSA slower than in control animals. Acid-base imbalances significantly affected the renal accumulation of DMSA, and acidosis was associated with markedly increased background due to increased liver accumulation. The protein-bound portion of 99mTc DMSA in the plasma was high, reaching 89% within the first 5 min, and rising very slightly (n.s.) ith time. The unbound portion of DMSA had a plasma clearance slightly higher than the GFR. Ablation of large amounts of renal tissue, resulting in significant decreases in GFR, did not significantly affect the renal localization of DMSA in the intact portions of the kidneys. These data demonstrate that commonly encountered changes in acid-base balance and hydration will significantly alter the biologic distribution of 99mTc DMSA. These factors should be controlled when carrying out clinical studies.

  13. 99mTc-DMSA Uptake in a Sister Mary Joseph's Nodule From Ovarian Cancer.

    PubMed

    Naddaf, Sleiman; Azzumeea, Fahad; Fahad Alzayed, Mohammed

    2016-12-01

    A 50-year-old woman with ovarian cancer underwent Tc-DMSA scan to evaluate the functional status of the right hydronephrotic kidney. The images incidentally revealed a well-defined focus of mild radiotracer uptake at the midanterior abdominal wall, which correlated with a metastatic Sister Mary Joseph's nodule seen on CT performed a week earlier.

  14. Simple and reliable method for determination of oxygen content in high- Tc copper oxides

    NASA Astrophysics Data System (ADS)

    Maeno, Yoshiteru; Teraoka, Hideki; Matsukuma, Kuniko; Yoshida, Koji; Sugiyama, Kimihiko; Nakamura, Fumihiko; Fujita, Toshizo

    1991-12-01

    We present the details of a simple and reliable iodine-titration method suited for high- Tc copper oxides, in which the use of a solution of ammonium acetate and acetic acid as a buffer agent substantially improves the operation. The results applied to La 2- xM xCuO 4- δ (M = Ba, Sr and Ca) are presented.

  15. {sup 99}Tc bioassay by inductively coupled plasma mass spectrometry (ICP-MS)

    SciTech Connect

    Lewis, L.A.

    1998-05-01

    A means of analyzing {sup 99}Tc in urine by inductively coupled plasma mass spectrometry (ICP-MS) has been developed. Historically, {sup 99}Tc analysis was based on the radiometric detection of the 293 keV E{sub Max} beta decay product by liquid scintillation or gas flow proportional counting. In a urine matrix, the analysis of{sup 99}Tc is plagued with many difficulties using conventional radiometric methods. Difficulties originate during chemical separation due to the volatile nature of Tc{sub 2}O{sub 7} or during radiation detection due to color or chemical quenching. A separation scheme for {sup 99}Tc detection by ICP-MS is given and is proven to be a sensitive and robust analytical alternative. A comparison of methods using radiometric and mass quantitation of {sup 99}Tc has been conducted in water, artificial urine, and real urine matrices at activity levels between 700 and 2,200 dpm/L. Liquid scintillation results based on an external standard quench correction and a quench curve correction method are compared to results obtained by ICP-MS. Each method produced accurate results, however the precision of the ICP-MS results is superior to that of liquid scintillation results. Limits of detection (LOD) for ICP-MS and liquid scintillation detection are 14.67 and 203.4 dpm/L, respectively, in a real urine matrix. In order to determine the basis for the increased precision of the ICP-MS results, the detection sensitivity for each method is derived and measured. The detection sensitivity for the {sup 99}Tc isotope by ICP-MS is 2.175 x 10{sup {minus}7} {+-} 8.990 x 10{sup {minus}9} and by liquid scintillation is 7.434 x 10{sup {minus}14} {+-} 7.461 x 10{sup {minus}15}. A difference by seven orders of magnitude between the two detection systems allows ICP-MS samples to be analyzed for a period of 15 s compared to 3,600 s by liquid scintillation counting with a lower LOD.

  16. Strain effect on the Néel temperature of SrTcO3 from first-principles calculations

    NASA Astrophysics Data System (ADS)

    Ma, Chun-Lan; Dai, Cheng-Min; Chen, Gao-Yuan; Chen, Da; Zang, Tao-Cheng; Ge, Li-Juan; Zhou, Wei; Zhu, Yan

    2015-10-01

    Generalized gradient approximation with on-site Coulomb corrections (GGA+U) method is used to investigate the effect of biaxial strain on the Néel temperature of SrTcO3. A series of hypothetical strains on SrTcO3 are considered to simulate its being applied in SrTcO3-based devices. It is found that a tensile strain will decrease TN, while a compressive strain less than 6.6% will increase TN. At a compressive strain between 5.5% and 6.7%, a highest TN which is about 26.6% higher than that of the bulk material can be obtained. The higher TN can be experimentally achieved by growing SrTcO3 on the common substrate STO/LSAT/NGO/LAO. Our work provides a theoretical basis for the application of high-TN SrTcO3 in small devices.

  17. Hypertension in children. Increased efficacy of technetium Tc/sup 99m/ succimer in screening for renal disease

    SciTech Connect

    Rosen, P.R.; Treves, S.; Ingelfinger, J.

    1985-02-01

    Renal scintigraphy with technetium Tc-99m succimer (DMSA) and technetium Tc-99m pentetate (DTPA) was used to study 80 hypertensive pediatric and adolescent patients. Renal abnormalities such as asymmetry of function, size, or shape were identified in 13 patients. Both excretory urography and technetium Tc-99m pentetate studies were successful in detecting 54% of the abnormalities in patients studied; technetium Tc-99m succimer identified 92%. The accuracy of the latter was 96%, with a specificity of 97%. The ability of technetium Tc-99m succimer renal scintigraphy to identify accurately the presence or absence of renal abnormalities warrants its inclusion in the initial examination of pediatric and adolescent patients with hypertension.

  18. Migrating data from TcSE to DOORS : an evaluation of the T-Plan Integrator software application.

    SciTech Connect

    Post, Debra S.; Manzanares, David A.; Taylor, Jeffrey L.

    2011-02-01

    This report describes our evaluation of the T-Plan Integrator software application as it was used to transfer a real data set from the Teamcenter for Systems Engineering (TcSE) software application to the DOORS software application. The T-Plan Integrator was evaluated to determine if it would meet the needs of Sandia National Laboratories to migrate our existing data sets from TcSE to DOORS. This report presents the struggles of migrating data and focuses on how the Integrator can be used to map a data set and its data architecture from TcSE to DOORS. Finally, this report describes how the bulk of the migration can take place using the Integrator; however, about 20-30% of the data would need to be transferred from TcSE to DOORS manually. This report does not evaluate the transfer of data from DOORS to TcSE.

  19. Influence of drying conditions of zirconium molybdate gel on performance of (99m)Tc gel generator.

    PubMed

    Davarpanah, M R; Attar Nosrati, S; Fazlali, M; Kazemi Boudani, M; Khoshhosn, H; Ghannadi Maragheh, M

    2009-10-01

    (99m)Tc can be produced from (99)Mo/(99m)Tc gel generators. These gels are part of the generator and the (99)Mo/(99m)Tc gel generator performance is directly related with gel structure. In this work a series of zirconium molybdate gels have been synthesized and dried under different conditions and characterized using thermal analysis (TGA, DTA), SEM, XRD and porosity measurements. It is found that the water content of the gel determines the structure porosity which allows the diffusion of the (99m)TcO(4)(-) ions inside the gel and was directly connected with performance of the (99)Mo/(99m)Tc gel generators. Drying conditions of the gel is as an important factor that influence water content and physical-chemical properties of this gel and must be carefully studied to optimize the properties of the gel generators.

  20. Physical phantom evaluation of simultaneous 99mTc/ 123I SPECT imaging

    NASA Astrophysics Data System (ADS)

    Yang, Bang-Hung; Wang, Shyh-Jen; Lee, Jhih-Shian; Jan, Meei-Ling; Chang, Chia-Jung; Chen, Jyh-Cheng

    2011-10-01

    Simultaneous dual-isotope imaging from two different energy gamma rays such as 99mTc and 123I is a promising technology in nuclear medicine. Its advantages are to abbreviate the acquisition procedure with an identical geometrical registration of the different isotope images, the same physiological condition without motion artifacts, and help patient throughput and comfort. However, the energy photopeaks of 99mTc and 123I radionuclides are very close. We had developed a new approach for accurate cross-talk and scatter corrections in simultaneous 99mTc/ 123I based on independent components analysis (ICA). Nevertheless, a large number of input energy windows are required as ICA input components, which is not useful in clinical application because commercial cameras have only 3-8 energy windows. The aim of this work was to design a new method through wavelet transformation followed by ICA with multiple energy windows (W_eICA) for cross-talk and scatter correction using a smaller number of energy windows in clinical use. There were three cylinders (A-C) with identical volume of 20 ml. Cylinder A was filled with 99mTc solution of 18.5 MBq, cylinder B with 123I solution of 18.5 MBq, and cylinder C with 99mTc solution of 55.5 MBq. The Image matrix size was 128×128 and pixel size was 3.9 mm. Three kinds of images were acquired by energy window setting. (1) For single-isotope imaging only, energy windows of 20% centered at 140 keV for 99mTc and at 159 keV for 123I were used. (2) In the asymmetric energy window method (AEW), energy window of 15% centered at 140 keV for 99mTc in conjunction with 10% asymmetric energy window in an upper bound at 159 keV for 123I was acquired. (3) Then we set six energy windows with 15 keV width ranging from 83 to 173 keV to form six images as input components of ICA. After the W_eICA method derived 99mTc/ 123I images alone, we compared the images from the W_eICA approach and the AEW method. In the results, the recovery rate of 99mTc was 1

  1. Reductive Sequestration Of Pertechnetate (99TcO4–) By Nano Zerovalent Iron (nZVI) Transformed By Abiotic Sulfide

    SciTech Connect

    Fan, Dimin; Anitori, Roberto; Tebo, Bradley M.; Tratnyek, Paul G.; Lezama Pacheco, Juan S.; Kukkadapu, Ravi K.; Engelhard, Mark H.; Bowden, Mark E.; Kovarik, Libor; Arey, Bruce W.

    2013-04-24

    Under anoxic conditions, soluble 99TcO4– can be reduced to less soluble TcO2•nH2O, but the oxide is highly susceptible to reoxidation. Here we investigate an alternative strategy for remediation of Tc-contaminated groundwater whereby sequestration as Tc sulfide is favored by sulfidic conditions stimulated by nano zero-valent iron (nZVI). nZVI was pre-exposed to increasing concentrations of sulfide in simulated Hanford groundwater for 24 hrs to mimic the stages of aquifer sulfate reduction and onset of biotic sulfidogenesis. Solid-phase characterizations of the sulfidated nZVI confirmed the formation of nanocrystalline FeS phases, but higher S/Fe ratios (>0.112) did not result in the formation of significantly more FeS. The kinetics of Tc sequestration by these materials showed faster Tc removal rates with increasing S/Fe between S/Fe = 0–0.056, but decreasing Tc removal rates with S/Fe > 0.224. The more favorable Tc removal kinetics at low S/Fe could be due to a higher affinity of TcO4– for FeS (over iron oxides), and electron microscopy confirmed that the majority of the Tc was associated with FeS phases. The inhibition of Tc removal at high S/Fe appears to have been caused by excess HS–. X-ray absorption spectroscopy revealed that as S/Fe increased, Tc speciation shifted from TcO2•nH2O to TcS2. The most substantial change of Tc speciation occurred at low S/Fe, coinciding with the rapid increase of Tc removal rate. This agreement further confirms the importance of FeS in Tc sequestration.

  2. Tumour angiogenesis is reduced in the Tc1 mouse model of Down's syndrome.

    PubMed

    Reynolds, Louise E; Watson, Alan R; Baker, Marianne; Jones, Tania A; D'Amico, Gabriela; Robinson, Stephen D; Joffre, Carine; Garrido-Urbani, Sarah; Rodriguez-Manzaneque, Juan Carlos; Martino-Echarri, Estefanía; Aurrand-Lions, Michel; Sheer, Denise; Dagna-Bricarelli, Franca; Nizetic, Dean; McCabe, Christopher J; Turnell, Andrew S; Kermorgant, Stephanie; Imhof, Beat A; Adams, Ralf; Fisher, Elizabeth M C; Tybulewicz, Victor L J; Hart, Ian R; Hodivala-Dilke, Kairbaan M

    2010-06-10

    Down's syndrome (DS) is a genetic disorder caused by full or partial trisomy of human chromosome 21 and presents with many clinical phenotypes including a reduced incidence of solid tumours. Recent work with the Ts65Dn model of DS, which has orthologues of about 50% of the genes on chromosome 21 (Hsa21), has indicated that three copies of the ETS2 (ref. 3) or DS candidate region 1 (DSCR1) genes (a previously known suppressor of angiogenesis) is sufficient to inhibit tumour growth. Here we use the Tc1 transchromosomic mouse model of DS to dissect the contribution of extra copies of genes on Hsa21 to tumour angiogenesis. This mouse expresses roughly 81% of Hsa21 genes but not the human DSCR1 region. We transplanted B16F0 and Lewis lung carcinoma tumour cells into Tc1 mice and showed that growth of these tumours was substantially reduced compared with wild-type littermate controls. Furthermore, tumour angiogenesis was significantly repressed in Tc1 mice. In particular, in vitro and in vivo angiogenic responses to vascular endothelial growth factor (VEGF) were inhibited. Examination of the genes on the segment of Hsa21 in Tc1 mice identified putative anti-angiogenic genes (ADAMTS1and ERG) and novel endothelial cell-specific genes, never previously shown to be involved in angiogenesis (JAM-B and PTTG1IP), that, when overexpressed, are responsible for inhibiting angiogenic responses to VEGF. Three copies of these genes within the stromal compartment reduced tumour angiogenesis, explaining the reduced tumour growth in DS. Furthermore, we expect that, in addition to the candidate genes that we show to be involved in the repression of angiogenesis, the Tc1 mouse model of DS will permit the identification of other endothelium-specific anti-angiogenic targets relevant to a broad spectrum of cancer patients.

  3. CD73-mediated adenosine production promotes stem cell-like properties in mouse Tc17 cells.

    PubMed

    Flores-Santibáñez, Felipe; Fernández, Dominique; Meza, Daniel; Tejón, Gabriela; Vargas, Leonardo; Varela-Nallar, Lorena; Arredondo, Sebastián; Guixé, Victoria; Rosemblatt, Mario; Bono, María Rosa; Sauma, Daniela

    2015-12-01

    The CD73 ectonucleotidase catalyses the hydrolysis of AMP to adenosine, an immunosuppressive molecule. Recent evidence has demonstrated that this ectonucleotidase is up-regulated in T helper type 17 cells when generated in the presence of transforming growth factor-β (TGF-β), and hence CD73 expression is related to the acquisition of immunosuppressive potential by these cells. TGF-β is also able to induce CD73 expression in CD8(+) T cells but the function of this ectonucleotidase in CD8(+) T cells is still unknown. Here, we show that Tc17 cells present high levels of the CD73 ectonucleotidase and produce adenosine; however, they do not suppress the proliferation of CD4(+) T cells. Interestingly, we report that adenosine signalling through A2A receptor favours interleukin-17 production and the expression of stem cell-associated transcription factors such as tcf-7 and lef-1 but restrains the acquisition of Tc1-related effector molecules such as interferon-γ and Granzyme B by Tc17 cells. Within the tumour microenvironment, CD73 is highly expressed in CD62L(+) CD127(+) CD8(+) T cells (memory T cells) and is down-regulated in GZMB(+) KLRG1(+) CD8(+) T cells (terminally differentiated T cells), demonstrating that CD73 is expressed in memory/naive cells and is down-regulated during differentiation. These data reveal a novel function of CD73 ectonucleotidase in arresting CD8(+) T-cell differentiation and support the idea that CD73-driven adenosine production by Tc17 cells may promote stem cell-like properties in Tc17 cells.

  4. Characterization of TcCYC6 from Trypanosoma cruzi, a gene with homology to mitotic cyclins.

    PubMed

    Di Renzo, María Agostina; Laverrière, Marc; Schenkman, Sergio; Wehrendt, Diana Patricia; Tellez-Iñón, María Teresa; Potenza, Mariana

    2016-06-01

    Trypanosoma cruzi, the etiologic agent of Chagas disease, is a protozoan parasite with a life cycle that alternates between replicative and non-replicative forms, but the components and mechanisms that regulate its cell cycle are poorly described. In higher eukaryotes, cyclins are proteins that activate cyclin-dependent kinases (CDKs), by associating with them along the different stages of the cell cycle. These cyclin-CDK complexes exert their role as major modulators of the cell cycle by phosphorylating specific substrates. For the correct progression of the cell cycle, the mechanisms that regulate the activity of cyclins and their associated CDKs are diverse and must be controlled precisely. Different types of cyclins are involved in specific phases of the eukaryotic cell cycle, preferentially activating certain CDKs. In this work, we characterized TcCYC6, a putative coding sequence of T. cruzi which encodes a protein with homology to mitotic cyclins. The overexpression of this sequence, fused to a tag of nine amino acids from influenza virus hemagglutinin (TcCYC6-HA), showed to be detrimental for the proliferation of epimastigotes in axenic culture and affected the cell cycle progression. In silico analysis revealed an N-terminal segment similar to the consensus sequence of the destruction box, a hallmark for the degradation of several mitotic cyclins. We experimentally determined that the TcCYC6-HA turnover decreased in the presence of proteasome inhibitors, suggesting that TcCYC6 degradation occurs via ubiquitin-proteasome pathway. The results obtained in this study provide first evidence that TcCYC6 expression and degradation are finely regulated in T. cruzi.

  5. (99m)Tc-DPD uptake reflects amyloid fibril composition in hereditary transthyretin amyloidosis.

    PubMed

    Pilebro, Björn; Suhr, Ole B; Näslund, Ulf; Westermark, Per; Lindqvist, Per; Sundström, Torbjörn

    2016-01-01

    Aims In transthyretin amyloid (ATTR) amyloidosis various principal phenotypes have been described: cardiac, neuropathic, or a mixed cardiac and neuropathic. In addition, two different types of amyloid fibrils have been identified (type A and type B). Type B fibrils have thus far only been found in predominantly early-onset V30M and in patients carrying the Y114C mutation, whereas type A is noted in all other mutations currently examined as well as in wild-type ATTR amyloidosis. The fibril type is a determinant of the ATTR V30M disease phenotype. (99m)Tc-DPD scintigraphy is a highly sensitive method for diagnosing heart involvement in ATTR amyloidosis. The objective of this study was to determine the relationship between ATTR fibril composition and (99m)Tc-DPD scintigraphy outcome in patients with biopsy-proven ATTR amyloidosis. Methods Altogether 55 patients with biopsy-proven diagnosis of ATTR amyloidosis and amyloid fibril composition determined were examined by (99m)Tc-DPD scintigraphy. The patients were grouped and compared according to their type of amyloid fibrils. Cardiovascular evaluation included ECG, echocardiography, and cardiac biomarkers. The medical records were scrutinized to identify subjects with hypertension or other diseases that have an impact on cardiac dimensions. Results A total of 97% with type A and none of the patients with type B fibrils displayed (99m)Tc-DPD uptake at scintigraphy (p < 0.001). Findings from analyses of cardiac biomarkers, ECG, and echocardiography, though significantly different, could not differentiate between type A and B fibrils in individual patients. Conclusion In ATTR amyloidosis, the outcome of (99m)Tc-DPD scintigraphy is strongly related to the patients' transthyretin amyloid fibril composition.

  6. Phase diagram and isotopic effect in high-Tc pnictide superconductors

    NASA Astrophysics Data System (ADS)

    Chen, Xianhui

    2010-03-01

    We will talk about the discovery of superconductivity with Tc higher than 40 K in Fe-based superconductors SmFeAsO1-xF. Tc higher than McMillan limit of 39 K definitely proves pnictide superconductors high-Tc superconductivity^1,2. In this talk, we present the transport properties: resistivity, Hall coefficient and transport properties under high magnetic field. These results suggest a quantum phase transition around x=0.14 in SmFeAsO1-xFx system. A electronic phase diagram is proposed, and coexistence of superconductivity and spin-density-wave is observed in Sm-1111 and Ba-122 system. We discuss the effect of isotopic effect on TC and TSDW in SmFeAsO1-xFx and Ba1-xKxFe2As2 systems. Our results show that oxygen isotope effect on TC and TSDW is very little, while the iron isotope exponent is about 0.35. Surprisingly, the iron isotope exchange shows the same effect on SDW transition as on superconductivity. Our results indicate that electron-phonon interaction plays some role in the superconducting mechanism, but simple electron-phonon coupling mechanism seems to be rather unlikely because a strong magnon-phonon coupling is included^3. 1. Chen, X. H. et al. Nature 453, 761-762 (2008). 2. Liu, R. H. et al. Phys. Rev. Lett. 101, 087001 (2008). 3. R. H. Liu et al., Nature 459, 64-67(2009).

  7. Magnetism in EuBCO and YBCO vortex states near and below Tc

    NASA Astrophysics Data System (ADS)

    Schwartz, R.; Browne, M. C.; Boekema, C.

    2012-02-01

    By means of MaxEnt-μSR [1] analysis, we investigate transverse field μSR data [2] of EuBa2Cu3O7-δgEuBCO; Tc = 93 K). Our focus is on a temperature interval near Tc to search for precursor effects, [3] and for predicted [4a] pseudogap loop currents above and below Tc, already observed [4b] above Tc for GdBCO. Further, we continue to study the field-direction dependence of the predicted [5a] and observed [5b] antiferromagnetism (AF) below 0.5Tc for the vortex states in c-axis-oriented YBCO. This AF in and near the vortex cores is likely three-dimensional. In sum, magnetic roots of cuprate superconductivity are well plausible. Research is supported by LANL-DOE, REU-NSF and AFC. [4pt] [1] C Boekema and MC Browne, AIP Conf Proc #1073 (2008) 260.[0pt] [2] DW Cooke et al, Phys Rev B 39 (1989) 2748.[0pt] [3] B Aguilar, C Boekema et al, Bull Am Phys Soc 37 (1992).[0pt] [4a] CM Varma, Phys Rev Lett 83 (1999) 3538.[0pt] [4b] T Songatikamas et al, J Supercond & Novel Magn 23 (2010) 793.[0pt] [5a] S-C Zhang, Science 275 (1997) 1089; H-D Chen et al, Phys Rev B70 (2004) 024516.[0pt] [5b] C. Boekema et al, J Phys Conf Series, 150 (2009) 052022. http://jpcs.iop.org/LT25

  8. Rapid diagnosis of occult abscesses using sup 99m Tc-labeled monoclonal antibodies

    SciTech Connect

    Coons, T.A.; Rhodes, B.A. ); Thakur, M.L. ); Marcus, C.S. ); Ballou, B. )

    1991-01-01

    Acute infections, such as appendicitis and occult infections in AIDS patients, can be diagnosed within two hours by gamma scintigraphy after i.v. administration of {sup 99m}Tc labeled antibodies reactive with human granulocytes. The antibody, murine IgM anti-SSEA-1, is partially reduced using Sn(II) to expose and protect reactive sulfide groups. The antibody is then purified, stannous tartrate and stabilizers are added, and the mixture is lyophilized. To label, sodium pertechnetate is added. After a 15 minute incubation the tracer drug is injected. The rate of accumulation and degree of concentration at the site of infection is presumptively determinative of the severity of the infection. Acceptance criteria and tests for the {sup 99m}Tc labeled antibody product have been established and validated. Greater than 93% of the {sup 99m}Tc is firmly bound to the protein as determined by quantitative HPLC. Radiochemical impurities, colloidal {sup 99m}Tc and free pertechnetate are together less than 4% as determined by thin layer chromatography. The immunoreactive fraction, measured by binding to solid phase antigen, and affinity measured be ELISA, are unchanged by the {sup 99m}Tc-direct labeling process. Two hour blood clearance in rats is within 90% of the value of the {sup 125}I labeled analog. The immunoreactive fraction decreases less than 10% when incubated in human plasma for 24 hours. This method has been compared to other direct labeling methods, and found to give higher radiochemical yields. 5 figs.

  9. Technical problems associated with the production of technetium Tc 99m tin(II) pyrophosphate kits

    SciTech Connect

    Kowalsky, R.J.; Dalton, D.R.

    1981-11-01

    The amount of tin(II) required for adequate reduction, complexation, and stability of technetium Tc 99m pertechnetate in radiopharmaceutical kits, and methods of preventing the loss of tin(II) during formulation of these lyophilized kits are investigated. Tin(II) loss from stannous chloride solutions was studied under several conditions, including room air versus nitrogen atmospheres, during vial filling in a laminar-flow hood with samples frozen on dry ice versus samples at room temperature, during lyophilization, and during storage under refrigerated, ambient, and elevated temperatures. Various amounts of stannous chloride, ranging from 5 to 1000 microgram/ml, were used in formulating sodium pertechnetate Tc 99m kits containing 100 mCi technetium Tc 99m and 0.4 microgram total technetium. Samples were removed at various times; hydrolyzed technetium, pertechnetate, and technetium Tc 99m pyrophosphate were isolated on instant thin-layer chromatography-silica gel and quantified with a scintillation counter. The time necessary to deoxygenate distilled water by nitrogen purging was measured. Several sources of stannous chloride were assayed for tin(II) content. Tin(II) loss occurs rapidly in solution (15% in one hour) unless continuously protected with nitrogen, and during vial filling in a laminar-flow hood unless frozen with dry ice. No substantial loss of tin(II) was detected during lyophilization or during storage of lyophilized product at any of the three temperatures. A minimum of 400 microgram tin(II) was required to provide 90% technetium Tc 99m pyrophosphate at six hours after preparation. Adequate deoxygenation of small quantities (450 ml) of water was accomplished in less than one hour. Some stannous chloride salts were highly oxidized in the dry state, and only high-purity elemental tin wire gave acceptable yields of tin(II).

  10. Technical problems associated with the production of technetium Tc 99m tin(II) pyrophosphate kits.

    PubMed

    Kowalsky, R J; Dalton, D R

    1981-11-01

    The amount of tin(II) required for adequate reduction, complexation, and stability of technetium Tc 99m pertechnetate in radiopharmaceutical kits, and methods of preventing the loss of tin(II) during formulation of these lyophilized kits are investigated. Tin(II) loss from stannous chloride solutions was studied under several conditions, including room air versus nitrogen atmospheres, during vial filling in a laminar-flow hood with samples frozen on dry ice versus samples at room temperature, during lyophilization, and during storage under refrigerated, ambient, and elevated temperatures. Various amounts of stannous chloride, ranging from 5 to 1000 microgram/ml, were used in formulating sodium pertechnetate Tc 99m kits containing 100 mCi technetium Tc 99m and 0.4 microgram total technetium. Samples were removed at various times; hydrolyzed technetium, pertechnetate, and technetium Tc 99m pyrophosphate were isolated on instant thin-layer chromatography-silica gel and quantified with a scintillation counter. The time necessary to deoxygenate distilled water by nitrogen purging was measured. Several sources of stannous chloride were assayed for tin(II) content. Tin(II) loss occurs rapidly in solution (15% in one hour) unless continuously protected with nitrogen, and during vial filling in a laminar-flow hood unless frozen with dry ice. No substantial loss of tin(II) was detected during lyophilization or during storage of lyophilized product at any of the three temperatures. A minimum of 400 microgram tin(II) was required to provide 90% technetium Tc 99m pyrophosphate at six hours after preparation. Adequate deoxygenation of small quantities (450 ml) of water was accomplished in less than one hour. Some stannous chloride salts were highly oxidized in the dry state, and only high-purity elemental tin wire gave acceptable yields of tin(II).

  11. Trichocystatin-2 (TC-2): an endogenous inhibitor of cysteine proteinases in Trichomonas vaginalis is associated with TvCP39.

    PubMed

    Puente-Rivera, Jonathan; Ramón-Luing, Lucero de los Ángeles; Figueroa-Angulo, Elisa Elvira; Ortega-López, Jaime; Arroyo, Rossana

    2014-09-01

    The causal agent of trichomoniasis is a parasitic protist, Trichomonas vaginalis, which is rich in proteolytic activity, primarily carried out by cysteine proteases (CPs). Some CPs are known virulence factors. T. vaginalis also possesses three genes encoding endogenous cystatin-like CP inhibitors. The aim of this study was to identify and characterize one of these CP inhibitors. Using two-dimensional gel electrophoresis (2-DE) and mass spectrometry (MS), a cystatin-like peptidase inhibitor dubbed Trichocystatin-2 (TC-2) was identified in the T. vaginalis active degradome in association with TvCP39, a 39kDa CP involved in cytotoxicity. To characterize the TC-2 inhibitor, we cloned and expressed the tvicp-2 gene, purified the recombinant protein (TC-2r), and produced a specific polyclonal antibody (α-TC-2r). This antibody recognized a 10kDa protein band by western blotting. An indirect immunofluorescence assay (IFA) and cell fractionation assays using the α-TC-2r antibody showed that TC-2 was localized in the cytoplasm and lysosomes and that it colocalized with TvCP39. TC-2r showed inhibitory activity against papain, cathepsin-L, and TvCP39 in trichomonad extracts and live parasites but not legumain-like CPs. Live trichomonads treated with TC-2r showed reduced trichomonal cytotoxicity to HeLa cell monolayers in a TC-2r-concentration-dependent manner. In this study, we identified and characterized an endogenous cystatin-like inhibitor in T. vaginalis, TC-2, which is associated with TvCP39 and appears to regulate the cellular damage caused by T. vaginalis.

  12. Cyclotron production of ⁹⁹mTc: recycling of enriched ¹⁰⁰Mo metal targets.

    PubMed

    Gagnon, K; Wilson, J S; Holt, C M B; Abrams, D N; McEwan, A J B; Mitlin, D; McQuarrie, S A

    2012-08-01

    There is growing interest in the large scale cyclotron production of (99m)Tc via the (100)Mo(p,2n)(99m)Tc reaction. While the use and recycling of cyclotron-irradiated enriched molybdenum targets has been reported previously in the context of (94m)Tc production, to the best of our knowledge, previous recycling studies have been limited to the use of oxide targets. To facilitate reuse of high-power enriched (100)Mo targets, this work presents and evaluates a strategy for recycling of enriched metallic molybdenum. For the irradiated (100)Mo targets in this study, an overall metal to metal recovery of 87% is reported. Evaluation of "new" and "recycled" (100)Mo revealed no changes in the molybdenum isotopic composition (as measured via ICP-MS). For similar irradiation conditions of "new" and "recycled" (100)Mo, (i.e. target thicknesses, irradiation time, and energy), comparable levels of (94g)Tc, (95g)Tc, and (96g)Tc contaminants were observed. Comparable QC specifications (i.e. aluminum ion concentration, pH, and radiochemical purity) were also reported. We finally note that [(99m)Tc]-MDP images obtained by comparing MDP labelled with generator-based (99m)Tc vs. (99m)Tc obtained following the irradiation of recycled (100)Mo demonstrated comparable biodistribution. With the goal of producing large quantities of (99m)Tc, the proposed methodology demonstrates that efficient recycling of enriched metallic (100)Mo targets is feasible and effective.

  13. A large renal pelvic diverticulum, presenting incomplete excretion during tc-99m MAG-3 scintigraphy and tracer accumulation on tc-99m DMSA scintigraphy; a case report.

    PubMed

    Turgut, Bulent; Erselcan, Taner; Ozdemir, Semra; Hasbek, Zekiye; Tosun, H Bayram; Topaktas, Seher

    2004-12-01

    This case report illustrates the dynamic and static renal scintigraphic images of a patient with an unusual large diverticulum of the renal pelvis. The initial diagnosis by intravenous pyelography (IVP) and ultrasonographic (US) examination was a renal pelvic diverticulum of the left kidney, and the patient was referred to the nuclear medicine department for exploration of the effect of the pelvic diverticulum on renal functions. We performed dynamic renal scintigraphy with technetium-99m (Tc-99m) labeled mercaptoacetyl triglycine (MAG-3) and static renal scintigraphy with Tc-99m labeled dimercaptosuccinic acid (DMSA). In dynamic renal scintigraphy, bilaterally normal concentration function was observed. While right kidney excretion function was normal, an incomplete excretion pattern was seen on the left side. Complete urinary flow obstruction occurred approximately at the 10th minute of the acquisition, which did not seem to respond to the i.v. furosemide application. However, when only the renal cortex was included in the region of interest, the obstructive pattern disappeared. In static renal scintigraphy, a large renal pelvic diverticulum localized antero-medially was clearly visualized in the left-anterior oblique projection, most probably due to accumulation of radiopharmaceutical inside it. This case showed that a renal pelvic diverticulum should be thought of when an incomplete excretion pattern is seen on dynamic renal scintigraphy. Using only a cortical region of interest may also help to distinguish other types of obstructive pattern from diverticulum. Additionally, Tc-99m DMSA scintigraphy may show diverticulum localization with antero-oblique projections in addition to routine projections.

  14. New series of Tc-99m-labeled hepatobiliary tracers: N'-acyl- and N'-sulfonyl ethylenediamine-N,N-diacetic acids

    SciTech Connect

    Karube, Y.; Kono, A.; Maeda, T.; Ohya, M.; Matsushima, Y.

    1981-07-01

    Various Tc-99m-labeled N'-substituted derivatives of ethylenediamine-N,N-diacetic acid (EDDA) are evaluated as hepatobiliary imaging agents. N'-substituted aromatic acyl and aromatic sulfonyl derivatives of EDDA, labeled with Tc-99m, were administered to rabbits and golden hamsters, and the distribution indicated clearance by the hepatobiliary system. N'-aromatic sulfonyl EDDAs were labeled with Tc-99m by the SnCl/sub 2/ method with more than 99% yield. Clearance of Tc-99m-p-toluenesulfonyl EDDA from the blood and the liver was as rapid as that of Tc-99m N-(2,6-diethylphenylcarbamoylmethyl)iminodiacetic acid (Tc-99m diethyl IDA). Substitution of a bulky group at the aromatic ring in Tc-99m benzene-sulfonyl EDDA lowered urinary excretion. It is concluded that the sulfonyl EDDAs provide a fruitful source for Tc-99m-labeled hepatobiliary radiopharmaceuticals.

  15. Luminescence-Based Spectroelectrochemical Sensor for [Tc(dmpe)3]2+/+ (dmpe = 1,2-bis(dimethylphosphino)ethane) within a Charge-Selective Polymer Film

    SciTech Connect

    Chatterjee, Sayandev; Del Negro, Andrew S.; Edwards, Matthew K.; Bryan, Samuel A.; Kaval, Necati; Pantelic, Nebojsa; Morris, Laura K.; Heineman, W. R.; Seliskar, Carl J.

    2011-03-01

    A spectroelectrochemical sensor consisting of an indium tin oxide (ITO) optically transparent electrode (OTE) coated with a thin film of sulfonated polystyrene-blockpoly(ethylene-ran-butylene)-block-polystyrene (SSEBS) was developed for [Tc(dmpe)3]+.. [Tc(dmpe)3]+ preconcentrated by ion-exchange into the SSEBS film after 20 min exposure to aqueous [Tc(dmpe)3]+ solution, resulting in a 14-fold increase in cathodic peak current compared to a bare OTE. Colorless [Tc(dmpe)3]+ was reversibly oxidized to colored [Tc(dmpe)3]2+ by cyclic voltammetry. Detection of [Tc(dmpe)3]2+ was accomplished by electrochemically cycling the complex between non-emissive [Tc(dmpe)3]+ and emissive [Tc(dmpe)3]2+ and monitoring the modulated emission (λexc = 532 nm; λem = 660 nm). The sensor gave a linear response over the range of 0.16 to 340.0 µM.

  16. Photochemical behavior of the quadruply metal-metal bonded [Tc2Cl8]2– anion in acetonitrile

    SciTech Connect

    Burton-Pye, Benjamin P.; Poineau, Frederic; Bertoia, Julie; Czerwinski, Kenneth R.; Francesconi, Lynn C.; Sattelberger, Alfred P.

    2016-09-23

    Here, the photochemical behavior of [Tc2Cl8]2– was investigated in acetonitrile. The speciation of Tc before and after irradiation at 254 nm was performed by UV-visible spectroscopy and electrospray ionization mass spectrometry (ESI-MS). Upon irradiation at 254 nm, [Tc2Cl8]2– was unstable, the scission of the TcTc unit occurred and the complex [TcCl4(CH3CN)2] was identified. The disappearance rate of [M2Cl8]2– (M = Tc, Re) under irradiation has been measured and was ~7.5 time faster for Tc than for Re.

  17. 99mTc Labeled Glucagon-Like Peptide-1-Analogue (99mTc-GLP1) Scintigraphy in the Management of Patients with Occult Insulinoma

    PubMed Central

    Sowa-Staszczak, Anna; Trofimiuk-Müldner, Małgorzata; Stefańska, Agnieszka; Tomaszuk, Monika; Buziak-Bereza, Monika; Gilis-Januszewska, Aleksandra; Jabrocka-Hybel, Agata; Głowa, Bogusław; Małecki, Maciej; Bednarczuk, Tomasz; Kamiński, Grzegorz; Kowalska, Aldona; Mikołajczak, Renata; Janota, Barbara; Hubalewska-Dydejczyk, Alicja

    2016-01-01

    Introduction The aim of this study was to assess the utility of [Lys40(Ahx-HYNIC-99mTc/EDDA)NH2]-exendin-4 scintigraphy in the management of patients with hypoglycemia, particularly in the detection of occult insulinoma. Materials and Methods Forty patients with hypoglycemia and increased/confusing results of serum insulin and C-peptide concentration and negative/inconclusive results of other imaging examinations were enrolled in the study. In all patients GLP-1 receptor imaging was performed to localise potential pancreatic lesions. Results Positive results of GLP-1 scintigraphy were observed in 28 patients. In 18 patients postsurgical histopathological examination confirmed diagnosis of insulinoma. Two patients had contraindications to the surgery, one patient did not want to be operated. One patient, who presented with postprandial hypoglycemia, with positive result of GLP-1 imaging was not qualified for surgery and is in the observational group. Eight patients were lost for follow up, among them 6 patients with positive GLP-1 scintigraphy result. One patient with negative scintigraphy was diagnosed with malignant insulinoma. In two patients with negative scintigraphy Munchausen syndrome was diagnosed (patients were taking insulin). Other seven patients with negative results of 99mTcGLP-1 scintigraphy and postprandial hypoglycemia with C-peptide and insulin levels within the limits of normal ranges are in the observational group. We would like to mention that 99mTc-GLP1-SPECT/CT was also performed in 3 pts with nesidioblastosis (revealing diffuse tracer uptake in two and a focal lesion in one case) and in two patients with malignant insulinoma (with the a focal uptake in the localization of a removed pancreatic headin one case and negative GLP-1 1 scintigraphy in the other patient). Conclusions 99mTc-GLP1-SPECT/CT could be helpful examination in the management of patients with hypoglycemia enabling proper localization of the pancreatic lesion and effective

  18. Osteomalacia-inducing renal clear cell carcinoma uncovered by 99mTc-Hydrazinonicotinyl-Tyr3-octreotide (99mTc-HYNIC-TOC) scintigraphy.

    PubMed

    Jin, Xiaona; Jing, Hongli; Li, Fang; Zhuang, Hongming

    2013-11-01

    Most osteomalacia-causing tumors are small, benign mesenchymal neoplasms, which are commonly located in the extremities or craniofacial regions. An 18-year-old male patient with suspicion of tumor-induced osteomalacia underwent (99m)Tc-HYNIC-TOC scintigraphy to search potential culprit tumor. The images showed a large activity in the region of the left kidney. The lesion was resected and a clear cell renal cell carcinoma was found. One year after the left nephrectomy, the patient was tumor-free without symptoms of osteomalacia.

  19. Minutes: Accredited Standards Committee on Acoustics, S1 U.S. Tag for ISO/TC43 Acoustics and IEC/TC29 Electroacoustics

    DTIC Science & Technology

    1991-05-02

    S3 meeting, Mr. Grason and Ms. Wilber also indicated their probable participation in the ISO/TC 43 meetings. 7. Review of Standards more than five...Brenig without all encl.: K. N. Eldred D. L. Johnson R. W. Krug A. H. Marsh L. A. Wilber G. S. K. Wong R. W. Young S1/347 ATTACHMENT C-6 Not for...1991. encl. cc: A. V. Brenig R. L. Grason L. A. Wilber No for Reproduction U.S.A./29(SEC.) 210 Original: English April 1991 S1/347 INTERNATIONAL

  20. Development of cell-based bioassay with Sf9 cells expressing TcSKR1 and TcSKR2 and differential activation by sulfated and non-sulfated SK peptides.

    PubMed

    Yu, Na; Swevers, Luc; Nachman, Ronald J; Smagghe, Guy

    2014-03-01

    Insect sulfakinin receptors (SKRs) are G-protein-coupled receptors (GPCRs) that interact with sulfakinins (SKs) to modulate diverse biological processes. One of the indispensable roles of SKs is in the regulation of food intake in insects. In this project we report on the development of a cell-based receptor assay system with insect Sf9 cells, expressing TcSKR1 and TcSKR2 from the red flour beetle Tribolium castaneum, a model and important pest insect in agriculture. In this system, a stable presence of the two TcSKRs was supported by Western blotting. The expressed TcSKRs were coupled to Gαs-protein upon activation and stimulated cAMP accumulation in Sf9 cells. Exposure of the transfected cell lines to sulfated SK (sSK) activated TcSKR1 at 1 nM; the EC50 of sSK to obtain 50% of receptor activation was similar for both receptors. In contrast, μM concentrations of non-sulfated SK were necessary to activate both TcSKRs. In conclusion, this cell-based TcSKR assay system is useful to screen SK-related peptides and mimetics and to better document ligand-receptor structure-activity relationships. Given the importance of SK signaling system in insects, the present study may provide new insights on the development of new methods to control pest insects.

  1. Successful Labeling of \\text{99mTc-MDP Using \\text{99mTc Separated from 99Mo Produced by 100Mo(n,2n)99Mo

    NASA Astrophysics Data System (ADS)

    Nagai, Yasuki; Hatsukawa, Yuichi; Kin, Tadahiro; Hashimoto, Kazuyuki; Motoishi, Shoji; Konno, Chikara; Ochiai, Kentaro; Takakura, Kosuke; Sato, Yuichi; Kawauchi, Yukimasa; Sato, Norihito; Ohta, Akio; Yamabayashi, Hisamichi; Tanase, Masakazu; Fujisaki, Saburo; Teranaka, Tomoyuki; Takeuchi, Nobuhiro; Igarashi, Takashi

    2011-08-01

    We have for the first time succeeded in separating \\text{99mTc from a MoO3 sample irradiated with accelerator neutrons free from any radioactive impurities and in formulating \\text{99mTc-methylene diphosphonate (\\text{99mTc-MDP). 99Mo, the mother nuclide of \\text{99mTc, was produced by the 100Mo(n,2n)99Mo reaction using about 14 MeV neutrons provided by the 3H(d,n)4He reaction at the Fusion Neutronics Source of Japan Atomic Energy Agency. The \\text{99mTc was separated from 99Mo by sublimation and its radionuclide purity was confirmed to be higher than 99.99% by γ-spectroscopy. The labeling efficiency of \\text{99mTc-MDP was shown to be higher than 99% by thin-layer chromatography. These values exceed the United States Pharmacopeia requirements for a fission product, 99Mo. Consequently, a \\text{99mTc radiopharmaceutical preparation formed by using the mentioned 99Mo can be a promising substitute for the fission product 99Mo, which is currently produced using a highly enriched uranium target in aging research reactors. A longstanding problem to ensure a reliable and constant supply of 99Mo in Japan can be partially mitigated.

  2. Quantitative simultaneous 99mTc/123I cardiac SPECT using MC-JOSEM.

    PubMed

    Ouyang, Jinsong; Zhu, Xuping; Trott, Cathryn M; El Fakhri, Georges

    2009-02-01

    Simultaneous rest 99mTc-Sestamibi/ 123I-BMIPP cardiac SPECT imaging has the potential to replace current clinical 99mTc-Sestamibi rest/stress imaging and therefore has great potential in the case of patients with chest pain presenting to the emergency department. Separation of images of these two radionuclides is difficult, however, because their emission energies are close. The authors previously developed a fast Monte Carlo (MC)-based joint ordered-subset expectation maximization (JOSEM) iterative reconstruction algorithm (MC-JOSEM), which simultaneously compensates for scatter and cross talk as well as detector response within the reconstruction algorithm. In this work, the authors evaluated the performance of MC-JOSEM in a realistic population of 99mTc/123I studies using cardiac phantom data on a Siemens e.cam system using a standard cardiac protocol. The authors also compared the performance of MC-JOSEM for estimation tasks to that of two other methods: standard OSEM using photopeak energy windows without scatter correction (NSC-OSEM) and standard OSEM using a Compton-scatter energy window for scatter correction (SC-OSEM). For each radionuclide the authors separately acquired high-count projections of radioactivity in the myocardium wall, liver, and soft tissue background compartments of a water-filled torso phantom, and they generated synthetic projections of various dual-radionuclide activity distributions. Images of different combinations of myocardium wall/background activity concentration ratios for each radionuclide were reconstructed by NSC-OSEM, SC-OSEM, and MC-JOSEM. For activity estimation in the myocardium wall, MC-JOSEM always produced the best relative bias and relative standard deviation compared with NSC-OSEM and SC-OSEM for all the activity combinations. On average, the relative biases after 100 iterations were 8.1% for 99mTc and 3.7% for 123I with MC-JOSEM, 39.4% for 99mTc and 23.7% for 123I with NSC-OSEM, and 20.9% for 99mTc with SC-OSEM. The

  3. Competitive Reduction of Pertechnetate (99TcO4- ) by Dissimilatory Metal Reducing Bacteria and Biogenic Fe(II)

    SciTech Connect

    Plymale, Andrew E.; Fredrickson, James K.; Zachara, John M.; Dohnalkova, Alice C.; Heald, Steve M.; Moore, Dean A.; Kennedy, David W.; Marshall, Matthew J.; Wang, Chongmin; Resch, Charles T.; Nachimuthu, Ponnusamy

    2011-01-06

    The fate of pertechnetate (99Tc(VII)O4-) during bioreduction was investigated in the presence of 2-line ferrihydrite (Fh) and various dissimilatory metal reducing bacteria (DMRB) (Geobacter, Anaeromyxobacter, Shewanella) in comparison with TcO4- bioreduction in the absence of Fh. In the presence of Fh, Tc was present primarily as a fine-grained Tc(IV)/Fe precipitate that was distinct from the Tc(IV)O2·nH2O solids produced by direct biological Tc(VII) reduction. Aqueous Tc concentrations (<0.2 μm) in the bioreduced Fh suspensions (1.7 to 3.2 × 10-9 mol L-1) were over 1 order of magnitude lower than when TcO4- was biologically reduced in the absence of Fh (4.0 × 10-8 to 1.0 × 10-7 mol L-1). EXAFS analyses of the bioreduced Fh-Tc products were consistent with variable chain length Tc-O octahedra bonded to Fe-O octahedra associated with the surface of the residual or secondary Fe(III) oxide. In contrast, biogenic TcO2·nH2O had significantly more Tc-Tc second neighbors and a distinct long-range order consistent with small particle polymers of TcO2. In Fe-rich subsurface sediments, the reduction of Tc(VII) by Fe(II) may predominate over direct microbial pathways, potentially leading to lower concentrations of aqueous 99Tc(IV).

  4. Two jasmonate-responsive factors, TcERF12 and TcERF15, respectively act as repressor and activator of tasy gene of taxol biosynthesis in Taxus chinensis.

    PubMed

    Zhang, Meng; Li, Shutao; Nie, Lin; Chen, Qingpu; Xu, Xiangping; Yu, Longjiang; Fu, Chunhua

    2015-11-01

    Methyl jasmonate (MeJA) is one of the most effective inducers of taxol biosynthetic genes, particularly the tasy gene. However, the mechanism underlying the regulation of tasy by MeJA is still unknown. In this study, a 550-bp 5'-flanking sequence was obtained and confirmed as the promoter of the tasy gene. Deletion analysis revealed that the fragment containing a GCC-box from -150 to -131 was the crucial jasmonate (JA)-responsive element, designated as JRE. Using JRE as bait, two binding proteins, namely TcERF12 and TcERF15, were discovered. Sequence alignment and phylogenetic analysis showed that TcERF12 was related to the repressor AtERF3, while TcERF15 was more related to the activator ORA59; these are typical GCC-box-binding ethylene-responsive factors. Both could significantly respond to MeJA for 10 and 4.5 times, respectively, in 0.5 h. When the two TcERFs were overexpressed in Taxus cells, tasy gene expression decreased by 2.1 times in TcERF12-overexpressing cells, but increased by 2.5 times in TcERF15-overexpressing cells. Results indicated that TcERF12 and TcERF15 were negative and positive regulators, respectively, in the JA signal transduction to the tasy gene by binding the GCC-box in the JRE of the tasy promoter. Our results promote further research on regulatory mechanisms of taxol biosynthesis.

  5. Detection of inflammatory lymph nodes in rabbits by 99mTc-HIG lymphoscintigraphy.

    PubMed

    Ergün, E L; Bozkurt, M F; Ercan, M T; Ruacan, S; Sener, B; Unsal, I S

    2002-12-01

    Tc-Human immunoglobulin G ( Tc-HIG) is a well-known radiopharmaceutical for the evaluation of inflammatory lesions. Recently, it has been demonstrated as a new agent for the visualization of the lymphatic system by our group. Our aim was to investigate the feasibility of detection of inflammatory lymph nodes by Tc-HIG lymphoscintigraphy. Ten adult New Zealand rabbits were used as group A. In a baseline study, 37 MBq Tc-HIG (0.1 ml) was injected into both hind legs of the rabbits, and sequential posterior gamma imaging with the rabbits lying prone was performed at 5, 15, 30, 60, 90 and 120 min using a single-headed gamma camera (Toshiba GCA G01 E). One week later, microorganisms ( ) were injected in a volume of 0.1 ml intradermally into the web space between the second and third toes in the bilateral hind legs of each rabbit in order to obtain inflammation in the popliteal lymph nodes. After 4 days, 37 MBq Tc-HIG (0.1 ml) was injected into the hind legs of the rabbits bilaterally, and sequential posterior gamma imaging was performed as described above (second study). Another group of 10 adult New Zealand rabbits (group B) was injected with the same microorganisms in the right hind legs only. After 4 days, scintigraphic imaging was carried out in the same way as described above (third study). Regions of interest were drawn over the injection sites and popliteal lymph nodes on each image for semiquantitative analysis. Count rates for each were calculated and a decay correction was applied. Time-activity curves were generated to show the percentage retention of radioactivity in each region. After the scintigraphic study, some of the group B rabbits were killed by intravenous injection of pentobarbitone (100-150 mg.kg, and both left and right lymph nodes were removed for microscopic examination. On the scintigrams, lymphatic channels and popliteal lymph nodes were visualized within 15 min. In the second study, bilateral popliteal lymph nodes were visualized more clearly

  6. Reduction of TcO4- by sediment-associated biogenic Fe(II)

    SciTech Connect

    Fredrickson, Jim K.; Zachara, John M.; Kennedy, David W.; Kukkadapu, Ravi K.; McKinley, James P.; Heald, Steve M.; Liu, Chongxuan; Plymale, Andrew E.

    2004-08-01

    The potential for reduction of {sup 99}TcO{sub 4}{sup -}{sub aq} to poorly soluble {sup 99}TcO{sub 2} {center_dot} nH{sub 2}O{sub (s)} by biogenic sediment-associated Fe(II) was investigated with three Fe(III)-oxide containing subsurface materials and the dissimilatory metal-reducing subsurface bacterium Shewanella putrefaciens CN32. Two of the subsurface materials from the U.S. Department of Energy's Hanford and Oak Ridge sites contained significant amounts of Mn(III,IV) oxides and net bioreduction of Fe(III) to Fe(II) was not observed until essentially all of the hydroxylamine HCl-extractable Mn was reduced. In anoxic, unreduced sediment or where Mn oxide bioreduction was incomplete, exogenous biogenic TcO{sub 2} {center_dot} nH{sub 2}O{sub (s)} was slowly oxidized over a period of weeks. Subsurface materials that were bioreduced to varying degrees and then pasteurized to eliminate biological activity, reduced TcO{sub 4}{sup -}{sub (aq)} at rates that generally increased with increasing concentrations of 0.5 N HCl-extractable Fe(II). Two of the sediments showed a common relationship between extractable Fe(II) concentration (in mM) and the first-order reduction rate (in h{sup -1}), whereas the third demonstrated a markedly different trend. A combination of chemical extractions and {sup 57}Fe Moessbauer spectroscopy were used to characterize the Fe(III) and Fe(II) phases. There was little evidence of the formation of secondary Fe(II) biominerals as a result of bioreduction, suggesting that the reactive forms of Fe(II) were predominantly surface complexes of different forms. The reduction rates of Tc(VII)O{sub 4}{sup -} were slowest in the sediment that contained plentiful layer silicates (illite, vermiculite, and smectite), suggesting that Fe(II) sorption complexes on these phases were least reactive toward pertechnetate. These results suggest that the in situ microbial reduction of sediment-associated Fe(III), either naturally or via redox manipulation, may be

  7. TC1(C8orf4) is a novel endothelial inflammatory regulator enhancing NF-kappaB activity.

    PubMed

    Kim, Jungtae; Kim, Yunlim; Kim, Hyun-Taek; Kim, Dong Wook; Ha, Yunhi; Kim, Jihun; Kim, Cheol-Hee; Lee, Inchul; Song, Kyuyoung

    2009-09-15

    Endothelial inflammation is regulated by a complex molecular mechanism. TC1(C8orf4) is a novel regulator implicated in cancer and inflammation. It is a small protein conserved well among vertebrates. In zebrafish embryos, it is mostly expressed in angio-hematopoietic system and the overexpression induces edema. In human aortic endothelial cells and umbilical vein endothelial cells, TC1 transfection up-regulates key inflammatory cytokines, enzymes, and adhesion proteins including IL-6, IL-1alpha, COX-2, CXCL1, CCL5, CCL2, IL-8, ICAM1, VCAM1, and E-selectin, while TC1 knockdown down-regulates them. TC1 also enhances inflammatory parameters such as monocyte-endothelial adhesion and endothelial monolayer permeability. TC1 is up-regulated by IL-1beta, TNF-alpha, LPS, and phorbol ester, and the up-regulation is inhibited by I-kappaB-kinase inhibitors. TC1, in turn, enhances the nuclear translocation of RelA and the DNA binding activity, suggesting a biological role of amplifying NF-kappaB signaling via a positive feedback. Our findings suggest that TC1 is a novel endothelial inflammatory regulator that might be implicated in inflammatory vascular diseases.

  8. Environmental applications of XANES: Speciation of {Tc} in cement after chemical treatment and Se after bacterial uptake

    SciTech Connect

    Shuh, D.K.; Kaltsoyannis, N.; Bucher, J.J.

    1994-03-01

    XANES (X-ray Absorption Near Edge Spectroscopy) has been employed to evaluate the efficacy of a process designed to encapsulate and reduce {Tc}O{sub 4}{sup {minus}} in cement matrices, thereby immobilizing {Tc}. The oxidation state of Se following.bioremediation of Se by bacteria has also been determined by XANES. The XANES measurements were performed at the Stanford Synchrotron Radiation Laboratory (SSRL) and the National Synchrotron Light Source (NSLS) at the respective K edges of {Tc} (21.0 keV) and Se (12.7 keV). Comparison of the XANES spectra of Tc in untreated cement to Tc in slag treated cement and to the chemical shifts of reference materials, shows that the oxidation state of {Tc} is the same in both cements. Thus, the addition of a reducing agent to the cement formulation does not significantly reduce the {Tc}O{sub 4} The common soil bacterium, Bacillus subtilis, is known to incorporate Se on or within the cell wall when exposed to a SE(IV) solution. The Se XANES spectra of B. subtilis, as well as bacillus isolated from selenium rich soil, show that the organisms reduce selenite to the red allotrope of elemental Se.

  9. The Chromosome-Encoded Hypothetical Protein TC0668 Is an Upper Genital Tract Pathogenicity Factor of Chlamydia muridarum

    PubMed Central

    Conrad, Turner Allen; Gong, Siqi; Yang, Zhangsheng; Matulich, Patrick; Keck, Jonathon; Beltrami, Noah; Chen, Chaoqun; Zhou, Zhou; Dai, Jin

    2015-01-01

    We previously associated a missense mutation of the tc0668 gene of serial in vitro-passaged Chlamydia muridarum, a murine model of human urogenital C. trachomatis, with severely attenuated disease development in the upper genital tract of female mice. Since these mutants also contained a TC0237 Q117E missense mutation that enhances their in vitro infectivity, an effort was made here to isolate and characterize a tc0668 single mutant to determine its individual contribution to urogenital pathogenicity. Detailed genetic analysis of C. muridarum passages revealed a truncated variant with a G216* nonsense mutation of the 408-amino-acid TC0668 protein that does not produce a detectable product. Intracellular growth and infectivity of C. muridarum in vitro remain unaffected in the absence of TC0668. Intravaginal inoculation of the TC0668 null mutant into C3H/HeJ mice results in a typical course of lower genital tract infection but, unlike a pathogenic isogenic control, is unable to elicit significant chronic inflammation of the oviduct and fails to induce hydrosalpinx. Thus, TC0668 is demonstrated as an important chromosome-encoded urogenital pathogenicity factor of C. muridarum and the first with these characteristics to be discovered for a Chlamydia pathogen. PMID:26597987

  10. Evidence for a dual role for TC4 protein in regulating nuclear structure and cell cycle progression

    PubMed Central

    1994-01-01

    TC4, a ras-like G protein, has been implicated in the feedback pathway linking the onset of mitosis to the completion of DNA replication. In this report we find distinct roles for TC4 in both nuclear assembly and cell cycle progression. Mutant and wild-type forms of TC4 were added to Xenopus egg extracts capable of assembling nuclei around chromatin templates in vitro. We found that a mutant TC4 protein defective in GTP binding (GDP-bound form) suppressed nuclear growth and prevented DNA replication. Nuclear transport under these conditions approximated normal levels. In a separate set of experiments using a cell-free extract of Xenopus eggs that cycles between S and M phases, the GDP- bound form of TC4 had dramatic effects, blocking entry into mitosis even in the complete absence of nuclei. The effect of this mutant TC4 protein on cell cycle progression is mediated by phosphorylation of p34cdc2 on tyrosine and threonine residues, negatively regulating cdc2 kinase activity. Therefore, we provide direct biochemical evidence for a role of TC4 in both maintaining nuclear structure and in the signaling pathways that regulate entry into mitosis. PMID:8188741

  11. Adsorption between TC-stabilized AuNPs and the phosphate group: application of the PTP1B activity assay.

    PubMed

    Lv, Jun; Wang, Xiaonan; Zhang, Yuanyuan; Li, Defeng; Zhang, Juan; Sun, Lizhou

    2015-12-07

    Based on the adsorption between tetracycline (TC) and phosphate groups, a general colorimetric method is explored in this work by using TC-stabilized gold nanoparticles (TC/AuNPs) and 4-aminophenyl phosphate-functionalized Fe3O4 magnetic nanoparticles (APP/MNPs). Taking protein tyrosine phosphatase 1B (PTP1B) as an example, 4-aminophenyl phosphate (APP) can be hydrolyzed into 4-aminophenol (AP) by PTP1B, resulting in the disappearance of the phosphate group on the outer layer of MNPs and the loss of corresponding adsorptive ability. Upon addition of TC/AuNP solution, TC/AuNPs will remain in the supernatant solution after magnetic separation and a high absorbance value can be observed. So PTP1B activity is related to the concentrations of TC/AuNPs in the supernatant solution. In this work, the enzyme activity can be determined at levels as low as 0.0885 U mL(-1) and over a linear detection range as wide as 0.1 U mL(-1) to 0.9 U mL(-1). Moreover, using the proposed method, the inhibition effect of betulinic acid (BA) and sodium orthovanadate (Na3VO4) on PTP1B activity can be tested with IC50 values of 30 μM and 4 μM, respectively. Therefore, a universal platform for the accurate colorimetric analysis of kinase and phosphatase activities can be established through the adsorption between TC and phosphate groups.

  12. Trypanosoma cruzi TcSMUG L-surface Mucins Promote Development and Infectivity in the Triatomine Vector Rhodnius prolixus

    PubMed Central

    Gonzalez, Marcelo S.; Souza, Marcela S.; Garcia, Eloi S.; Nogueira, Nadir F. S.; Mello, Cícero B.; Cánepa, Gaspar E.; Bertotti, Santiago; Durante, Ignacio M.; Azambuja, Patrícia; Buscaglia, Carlos A.

    2013-01-01

    Background TcSMUG L products were recently identified as novel mucin-type glycoconjugates restricted to the surface of insect-dwelling epimastigote forms of Trypanosoma cruzi, the etiological agent of Chagas disease. The remarkable conservation of their predicted mature N-terminal region, which is exposed to the extracellular milieu, suggests that TcSMUG L products may be involved in structural and/or functional aspects of the interaction with the insect vector. Methodology and Principal Findings Here, we investigated the putative roles of TcSMUG L mucins in both in vivo development and ex vivo attachment of epimastigotes to the luminal surface of the digestive tract of Rhodnius prolixus. Our results indicate that the exogenous addition of TcSMUG L N-terminal peptide, but not control T. cruzi mucin peptides, to the infected bloodmeal inhibited the development of parasites in R. prolixus in a dose-dependent manner. Pre-incubation of insect midguts with the TcSMUG L peptide impaired the ex vivo attachment of epimastigotes to the luminal surface epithelium, likely by competing out TcSMUG L binding sites on the luminal surface of the posterior midgut, as revealed by fluorescence microscopy. Conclusion and Significance Together, these observations indicate that TcSMUG L mucins are a determinant of both adhesion of T. cruzi epimastigotes to the posterior midgut epithelial cells of the triatomine, and the infection of the insect vector, R. prolixus. PMID:24244781

  13. The TcI and TcII Trypanosoma cruzi experimental infections induce distinct immune responses and cardiac fibrosis in dogs

    PubMed Central

    Duz, Ana Luiza Cassin; Vieira, Paula Melo de Abreu; Roatt, Bruno Mendes; Aguiar-Soares, Rodrigo Dian Oliveira; Cardoso, Jamille Mirelle de Oliveira; de Oliveira, Flávia Carvalho Bitencourt; Reis, Levi Eduardo Soares; Tafuri, Washington Luiz; Veloso, Vanja Maria; Reis, Alexandre Barbosa; Carneiro, Cláudia Martins

    2014-01-01

    Trypanosoma cruzi infection may be caused by different strains with distinct discrete typing units (DTUs) that can result in variable clinical forms of chronic Chagas disease. The present study evaluates the immune response and cardiac lesions in dogs experimentally infected with different T. cruzi strains with distinct DTUs, namely, the Colombian (Col) and Y strains of TcI and TcII DTU, respectively. During infection with the Col strain, increased levels of alanine aminotransferase, erythrocytes, haematocrit and haemoglobin were observed. In addition, CD8+ T-lymphocytes isolated from the peripheral blood produced higher levels of interleukin (IL)-4. The latter suggests that during the acute phase, infection with the Col strain may remain unnoticed by circulating mononuclear cells. In the chronic phase, a significant increase in the number of inflammatory cells was detected in the right atrium. Conversely, infection with the Y strain led to leucopoenia, thrombopoenia, inversion of the ratio of CD4+/CD8+ T-lymphocytes and alterations in monocyte number. The Y strain stimulated the production of interferon-γ by CD4+ and CD8+ T-lymphocytes and IL-4 by CD8+ T-cells. In the chronic phase, significant heart inflammation and fibrosis were observed, demonstrating that strains of different DTUs interact differently with the host. PMID:25591108

  14. (99m)Tc-zolmitriptan: radiolabeling, molecular modeling, biodistribution and gamma scintigraphy as a hopeful radiopharmaceutical for lung nuclear imaging.

    PubMed

    Rashed, H M; Marzook, F A; Farag, H

    2016-12-01

    Lung imaging radiopharmaceuticals are helpful agents for measuring pulmonary blood flow and allow detection of pulmonary embolism and lung cancer. The goal of this study was to develop a novel potential radiopharmaceutical for lung imaging. Zolmitriptan (a selective serotonin receptor agonist) was successfully labeled with (99m)Tc via direct labeling method under reductive conditions studying different factors affecting the labeling efficiency. (99m)Tc-zolmitriptan was obtained with a maximum labeling yield of 92.5 ± 0.61 % and in vitro stability up to 24 h. Molecular modeling was done to predict the structure of (99m)Tc-zolmitriptan and ensure that radiolabeling did not affect binding ability of zolmitriptan to its receptor. Biodistribution studies showed that maximum lung uptake of (99m)Tc-zolmitriptan was 23.89 ± 1.2 % injected dose/g tissue at 15 min post-injection and retention in lungs remained high up to 1 h, whereas the clearance from mice appeared to proceed mainly via the renal pathway. Scintigraphic images confirmed the biodistribution results showing a high resolution lung image with low accumulation of radioactivity in other organs except kidneys and urinary bladder. (99m)Tc-zolmitriptan is not a blood product and so it is more safe than the currently available (99m)Tc-MAA, and its lung uptake is higher than that of the recently discovered (123)I-IPMPD, (99m)Tc(CO)5I and (99m)Tc-DHPM. So, (99m)Tc-zolmitriptan could be used as a hopeful radiopharmaceutical for lung scintigraphic imaging.

  15. High 99mTc-DPD myocardial uptake in a patient with apolipoprotein AI-related amyloidotic cardiomyopathy.

    PubMed

    Quarta, Candida Cristina; Obici, Laura; Guidalotti, Pier Luigi; Pieroni, Maurizio; Longhi, Simone; Perlini, Stefano; Verga, Laura; Merlini, Giampaolo; Rapezzi, Claudio

    2013-03-01

    Amyloidotic cardiomyopathy is still a widely underdiagnosed condition that usually requires endomyocardial biopsy (EMB) for a definite diagnosis. 99mTc-3,3-diphosphono-1,2-propanodicarboxylic acid (99mTc-DPD) has proven highly sensitive for detecting amyloidotic cardiomyopathy due to transthyretin-related amyloid deposition. Herein we report the first description of the (99mTc-DPD scintigraphy profile in a patient with suspected amyloidotic cardiomyopathy and a final EMB- and genetically-proven diagnosis of familial apolipoprotein AI amyloidosis due to Leu174Ser variant.

  16. Phase stability, electronic structure and equation of state of cubic TcN from first-principles calculations

    NASA Astrophysics Data System (ADS)

    Song, T.; Ma, Q.; Sun, X. W.; Liu, Z. J.; Fu, Z. J.; Wei, X. P.; Wang, T.; Tian, J. H.

    2016-09-01

    The phase transition, electronic band structure, and equation of state (EOS) of cubic TcN are investigated by first-principles pseudopotential method based on density-functional theory. The calculated enthalpies show that TcN has a transformation between zincblende and rocksalt phases and the pressure determined by the relative enthalpy is 32 GPa. The calculated band structure indicates the metallic feature and it might make cubic TcN a better candidate for hard materials. Particular attention is paid to the predictions of volume, bulk modulus and its pressure derivative which play a central role in the formulation of approximate EOSs using the quasi-harmonic Debye model.

  17. Separation of [(99m)Tc]pertechnetate and molybdate using polyethylene glycol coated C18 and C30 resins.

    PubMed

    Andersson, J D; Wilson, J S; Romaniuk, J A; McEwan, A J B; Abrams, D N; McQuarrie, S A; Gagnon, K

    2016-04-01

    Hydrophobic adsorbents such as C18 and C30 were coated with PEG and subsequently used for the separation of Mo/Tc. The most effective resin for adsorbing PEG was the C18-U resin, which demonstrated a coating capacity of 97.6±2.8mg PEG per g of resin. The ability to adsorb pertechnetate was proportional to the amount of PEG coated on the hydrophobic resin. The [(99m)Tc]pertechnetate recovery during the separation of cyclotron produced (99m)Tc from (100)Mo was 91.8±0.3% (n=2). The resultant product met relevant USP monograph specifications.

  18. Application of AnaLig resin for (99m)Tc separation from (100)Mo target irradiated in cyclotron.

    PubMed

    Pawlak, D W; Wojdowska, W; Parus, L J; Mikołajczak, R

    2016-07-01

    The purpose of this study was the development of procedure for molybdenum metallic target processing after its irradiation in a cyclotron. As a first step the dissolution of molybdenum in various physical forms was investigated. The concentrations of NaOH and (NH4)2CO3 allowing the highest sorption of Tc on AnaLig Tc-02 resin had been found. Based on these results the sintered irradiated Mo pellet was processed. The radionuclidic and radiochemical purities of separated Tc product were evaluated.

  19. Activity measurements of the radionuclide 99mTc for the VNIIM, Russian Federation and ENEA-INMRI, Italy, in the ongoing comparison BIPM.RI(II)-K4.Tc-99m and KCRV update in the BIPM.RI(II)-K1.Tc-99m comparison

    NASA Astrophysics Data System (ADS)

    Michottea, C.; Nonisa, M.; Alekseevb, I. V.; Kharitonovb, I. A.; Tereshchenkob, E. E.; Zanevskiyb, A. V.; Capognic, M.; De Felicec, P.; Fazioc, A.; Carconic, P.

    2016-01-01

    In 2014, comparisons of activity measurements of 99mTc using the Transfer Instrument of the International Reference System (SIRTI) took place at the VNIIM (Russian Federation) and at the ENEA-INMRI (Italy), with comparison identifier BIPM.RI(II)-K4.Tc-99m. Ampoules containing about 32 kBq of 99mTc solutions were measured in the SIRTI for three half-lives. There are now nine results in the BIPM.RI(II)-K4.Tc-99m comparison. This comparison is linked to the BIPM.RI(II)-K1.Tc-99m comparison and the key comparison reference value (KCRV) of the BIPM.RI(II)-K1.Tc-99m has been updated to include eligible results from BIPM.RI(II)-K4.Tc-99m. The degrees of equivalence between each equivalent activity measured in the SIR or the SIRTI and the KCRV have been calculated and the results are given in the form of a table. A graphical presentation is also given. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  20. Quasiparticle mass enhancement approaching optimal doping in a high-Tc superconductor

    DOE PAGES

    Ramshaw, B. J.; Sebastian, S. E.; McDonald, R. D.; ...

    2015-03-26

    In the quest for superconductors with higher transition temperatures (Tc), one emerging motif is that electronic interactions favorable for superconductivity can be enhanced by fluctuations of a broken-symmetry phase. In recent experiments it is suggested that the existence of the requisite broken-symmetry phase in the high-Tc cuprates, but the impact of such a phase on the ground-state electronic interactions has remained unclear. Here, we used magnetic fields exceeding 90 tesla to access the underlying metallic state of the cuprate YBa2Cu3O6+δ over a wide range of doping, and observed magnetic quantum oscillations that reveal a strong enhancement of the quasiparticle effectivemore » mass toward optimal doping. Finally, this mass enhancement results from increasing electronic interactions approaching optimal doping, and suggests a quantum critical point at a hole doping of pcrit ≈ 0.18.« less