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Vidal AKF, Daher RF, Freitas RS, Santana JGS, Stida WF, Ambrósio M, Silva VB, Souza AG, Nascimento MR, Santos RM, Leite CL, Farias JEC. Genetic diversity based on multivariate techniques in elephant grass genotypes for bioenergy. BRAZ J BIOL 2024; 84:e278601. [PMID: 38422291 DOI: 10.1590/1519-6984.278601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 01/02/2024] [Indexed: 03/02/2024] Open
Abstract
The use of biomass for energy production constitutes a promising strategy that warrants the search for new sources of biomass. Elephant grass has been gaining notoriety due to its high dry matter yield and rapid growth. The present study was carried out to quantify the genetic divergence of nine elephant grass half-sib families in order to identify genotypes with greater genetic divergence and productive potential for hybridization, using the hierarchical clustering methodology based on principal components. Half-sib families were generated using genotypes from the Active Germplasm Bank of Elephant Grass. The experiment was laid out in a randomized-block design with nine half-sib families, three replicates, and eight plants per plot. A total of 216 genotypes of elephant grass were evaluated. Principal component (PC), biplot, and hierarchical clustering analyses for diversity estimation were conducted using R software. The first two PCs of biplot analysis accounted for 64% of the cumulative variation. Dry matter yield was the most important trait for genotype discrimination (0.89), followed by plant height (0.67) and stem diameter (0.61) in PC1. In this analysis, the distances between accessions were considered and there were no family links, which indicates the existence of wide variability within the evaluated families, since genotypes belonging to the same family were not grouped together, but rather distributed into different groups. Crosses between genotypes of group three and genotypes of groups one and two are recommended for the development of high-yielding genotypes when aiming at energy production.
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Affiliation(s)
- A K F Vidal
- Universidade Estadual do Norte Fluminense Darcy Ribeiro - UENF, Centro de Ciências e Tecnologias Agropecuárias - CCTA, Campos dos Goytacazes, RJ, Brasil
| | - R F Daher
- Universidade Estadual do Norte Fluminense Darcy Ribeiro - UENF, Centro de Ciências e Tecnologias Agropecuárias - CCTA, Campos dos Goytacazes, RJ, Brasil
| | - R S Freitas
- Universidade Estadual do Norte Fluminense Darcy Ribeiro - UENF, Centro de Ciências e Tecnologias Agropecuárias - CCTA, Campos dos Goytacazes, RJ, Brasil
| | - J G S Santana
- Universidade Estadual do Norte Fluminense Darcy Ribeiro - UENF, Centro de Ciências e Tecnologias Agropecuárias - CCTA, Campos dos Goytacazes, RJ, Brasil
| | - W F Stida
- Universidade Estadual do Norte Fluminense Darcy Ribeiro - UENF, Centro de Ciências e Tecnologias Agropecuárias - CCTA, Campos dos Goytacazes, RJ, Brasil
| | - M Ambrósio
- Universidade Estadual do Norte Fluminense Darcy Ribeiro - UENF, Centro de Ciências e Tecnologias Agropecuárias - CCTA, Campos dos Goytacazes, RJ, Brasil
| | - V B Silva
- Universidade Federal do Piauí - UFPI, Centro de Ciências Agrárias - CCA, Programa de Pós-graduação em Agronomia - PPGA, Campus Universitário Ministro Petrônio Portella, Teresina, PI, Brasil
| | - A G Souza
- Universidade Estadual do Norte Fluminense Darcy Ribeiro - UENF, Centro de Ciências e Tecnologias Agropecuárias - CCTA, Campos dos Goytacazes, RJ, Brasil
| | - M R Nascimento
- Universidade Estadual do Norte Fluminense Darcy Ribeiro - UENF, Centro de Ciências e Tecnologias Agropecuárias - CCTA, Campos dos Goytacazes, RJ, Brasil
| | - R M Santos
- Universidade Estadual do Norte Fluminense Darcy Ribeiro - UENF, Centro de Ciências e Tecnologias Agropecuárias - CCTA, Campos dos Goytacazes, RJ, Brasil
| | - C L Leite
- Universidade Estadual do Norte Fluminense Darcy Ribeiro - UENF, Centro de Ciências e Tecnologias Agropecuárias - CCTA, Campos dos Goytacazes, RJ, Brasil
| | - J E C Farias
- Universidade Estadual do Norte Fluminense Darcy Ribeiro - UENF, Centro de Ciências e Tecnologias Agropecuárias - CCTA, Campos dos Goytacazes, RJ, Brasil
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Rodrigues EV, Daher RF, Dos Santos A, Vivas M, Machado JC, Gravina GDA, de Souza YP, Vidal AK, Rocha ADS, Freitas RS. Selecting elephant grass families and progenies to produce bioenergy through mixed models (REML/BLUP). Genet Mol Res 2017; 16:gmr-16-02-gmr.16029301. [PMID: 28525651 DOI: 10.4238/gmr16029301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Brazil has great potential to produce bioenergy since it is located in a tropical region that receives high incidence of solar energy and presents favorable climatic conditions for such purpose. However, the use of bioenergy in the country is below its productivity potential. The aim of the current study was to select full-sib progenies and families of elephant grass (Pennisetum purpureum S.) to optimize phenotypes relevant to bioenergy production through mixed models (REML/BLUP). The circulating diallel-based crossing of ten elephant grass genotypes was performed. An experimental design using the randomized block methodology, with three repetitions, was set to assess both the hybrids and the parents. Each plot comprised 14-m rows, 1.40 m spacing between rows, and 1.40 m spacing between plants. The number of tillers, plant height, culm diameter, fresh biomass production, dry biomass rate, and the dry biomass production were assessed. Genetic-statistical analyses were performed through mixed models (REML/BLUP). The genetic variance in the assessed families was explained through additive genetic effects and dominance genetic effects; the dominance variance was prevalent. Families such as Capim Cana D'África x Guaçu/I.Z.2, Cameroon x Cuba-115, CPAC x Cuba-115, Cameroon x Guaçu/I.Z.2, and IAC-Campinas x CPAC showed the highest dry biomass production. The family derived from the crossing between Cana D'África and Guaçu/I.Z.2 showed the largest number of potential individuals for traits such as plant height, culm diameter, fresh biomass production, dry biomass production, and dry biomass rate. The individual 5 in the family Cana D'África x Guaçu/I.Z.2, planted in blocks 1 and 2, showed the highest dry biomass production.
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Affiliation(s)
- E V Rodrigues
- Embrapa Agroenergia, Parque Estação Biológica, , Brasil
| | - R F Daher
- Laboratório de Engenharia Agrícola, Centro de Ciências e Tecnologias Agropecuárias, , , Brasil
| | - A Dos Santos
- Laboratório de Melhoramento Genético Vegetal, Centro de Ciências e Tecnologias Agropecuárias, , , Brasil
| | - M Vivas
- Laboratório de Engenharia Agrícola, Centro de Ciências e Tecnologias Agropecuárias, , , Brasil
| | - J C Machado
- Empresa Brasileira de Pesquisa Agropecuária, Embrapa Gado de Leite, , Brasil
| | - G do A Gravina
- Laboratório de Engenharia Agrícola, Centro de Ciências e Tecnologias Agropecuárias, , , Brasil
| | - Y P de Souza
- Laboratório de Engenharia Agrícola, Centro de Ciências e Tecnologias Agropecuárias, , , Brasil
| | - A K Vidal
- Laboratório de Engenharia Agrícola, Centro de Ciências e Tecnologias Agropecuárias, , , Brasil
| | - A Dos S Rocha
- Laboratório de Engenharia Agrícola, Centro de Ciências e Tecnologias Agropecuárias, , , Brasil
| | - R S Freitas
- Laboratório de Engenharia Agrícola, Centro de Ciências e Tecnologias Agropecuárias, , , Brasil
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Paduan-Filho A, Vieira AP, Ramon JGA, Freitas RS. Crossover from one- to three-dimensional behavior in the S = 1/2 Heisenberg antiferromagnet Cu(N 2H 5) 2(SO 4) 2. J Phys Condens Matter 2016; 28:506004. [PMID: 27792667 DOI: 10.1088/0953-8984/28/50/506004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
From experimental and theoretical analyses of magnetic and specific-heat properties, we present the complete magnetic phase diagram of the quasi-1D antiferromagnet Cu(N2H5)2(SO4)2. On cooling and at zero magnetic field this compound enters a 1D regime with short-range magnetic correlations, marked by a broad maximum in the specific heat and magnetic susceptibility at [Formula: see text] K, followed by a tridimensional antiferromagnetically ordered phase below [Formula: see text] K induced by small interchain couplings. The intermediate-temperature 1D regime can be modeled using exact quantum-transfer-matrix calculations, which offer a compatible description of the nonmonotonic behavior of [Formula: see text] as a function of the magnetic field, giving [Formula: see text] K for the intrachain exchange parameter. The analysis of magnetic specific-heat and susceptibility data at low temperature indicates that the interchain exchange couplings are an order of magnitude smaller than the coupling inside the chains.
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Affiliation(s)
- A Paduan-Filho
- Instituto de Física, Universidade de São Paulo, 05314-970 São Paulo, Brazil
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Freitas RS, Paduan-Filho A, Becerra CC. Thermal behavior in the magnetic phase diagram of the easy axis antiferromagnet Cs₂FeCl₅·H₂O. J Phys Condens Matter 2016; 28:126007. [PMID: 26933909 DOI: 10.1088/0953-8984/28/12/126007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The specific heat at a constant applied field C(H)(T) and at fixed temperatures C(T)(H) of single crystals of the low anisotropy antiferromagnet Cs2FeCl5·H2O was measured across the different boundaries of its magnetic phase diagram, in magnetic fields up to 9 T applied parallel and perpendicular to the easy axis direction and to temperatures down to 0.3 K. The specific heat data indicate that the critical behavior along the antiferromagnetic to paramagnetic phase boundary and the spin-flop to paramagnetic phase boundary, are basically the same. We also measured the specific heat when the first order antiferromagnetic to spin-flop phase boundary is crossed at a fixed temperature. The entropy of the different magnetic phases is discussed.
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Affiliation(s)
- R S Freitas
- Instituto de Física Universidade de São Paulo CP 66318, 05314-970 São Paulo, SP, Brazil
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Ehlers G, Podlesnyak AA, Frontzek M, Freitas RS, Ghivelder L, Gardner JS, Shiryaev SV, Barilo S. A detailed study of the magnetic phase transition in CuCrO2. J Phys Condens Matter 2013; 25:496009. [PMID: 24214902 DOI: 10.1088/0953-8984/25/49/496009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The phase transition in CuCrO2 to an ordered magnetic state is studied with bulk measurements and elastic and inelastic neutron scattering techniques. The reported onset of spontaneous electric polarization at T = 23.5 K coincides with the appearance, on cooling, of elastic magnetic scattering. At higher temperatures long range magnetic correlations gradually develop but they are dynamic. The ground state is characterized by three-dimensional long range magnetic ordering but along the c direction the correlation length remains limited to ∼200 Å.
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Affiliation(s)
- G Ehlers
- Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831-6475, USA
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Artico G, Freitas RS, Santos Filho AM, Benard G, Romiti R, Migliari DA. Prevalence of Candida spp., xerostomia, and hyposalivation in oral lichen planus--a controlled study. Oral Dis 2013; 20:e36-41. [PMID: 23656547 DOI: 10.1111/odi.12120] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2013] [Revised: 04/07/2013] [Accepted: 04/14/2013] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To determine the frequency of Candida spp., xerostomia, and salivary flow rate (SFR) in three different groups: patients with OLP (OLP group), patients with oral mucosal lesions other than OLP (non-OLP group), and subjects without oral mucosal lesions (control group). MATERIAL AND METHODS Xerostomia as well as SFR was investigated in the three groups. Samples for isolation of Candida spp. were collected from OLP lesions (38 patients), non-OLP lesions (28 patients), and healthy subjects (32 subjects). RESULTS There was no statistically significant difference regarding the frequency of xerostomia and hyposalivation among the three groups (P > 0.05). A higher prevalence for colonization by Candida spp. was found in the healthy subject as compared to that of patients with OLP (P = 0.03) and non-OLP (P = 0.02) groups. Low SFR was not a factor for colonization by Candida spp. CONCLUSIONS Xerostomia and hyposalivation occur with similar frequency in subjects with and without oral lesions; also, the presence of oral lesions does not increase the susceptibility to colonization by Candida spp. It seems that any study implicating Candida spp. in the malignant transformation of oral lesions should be carried out mostly on a biochemical basis, that is, by testing the capability of Candida spp. to produce carcinogenic enzyme.
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Affiliation(s)
- G Artico
- Department of Stomatology, School of Dentistry, University of São Paulo, São Paulo, Brazil
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7
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Moreno SRF, Feliciano GD, Freitas RS, Mattos DM, Gomes ML, Farah MB, Laurentino-Filho GL, Rocha EK, Filho MB. Effect of ginkgo biloba on the in vitro labeling of red blood cells and plasma proteins with technetium-99M. J Labelled Comp Radiopharm 2012. [DOI: 10.1002/jlcr.25804401226] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Freitas RS, Gomes ML, Mattos DM, Moreno SR, Feliciano GD, Lima E, Lima-Filho GL, Penas ME, Orlando MMC, Bernardo-Filho M. Comparison of the precipitation methods (ammonium sulphate and trichloroacetic acid) to evaluate the in vivo binding of 99mTc-MDP on blood constituents. J Labelled Comp Radiopharm 2012. [DOI: 10.1002/jlcr.25804401216] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Mattos DMM, Gomes ML, Freitas RS, Moreno S, Nascimento ALR, Carvalho JJ, Bernardo-Filho M. Vincristine toxicity: The effect on the biodistribution of radiopharma ceutical and in the optical microscopy of organs isolated from the treated animals. J Labelled Comp Radiopharm 2012. [DOI: 10.1002/jlcr.25804401169] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Mattos DMM, Gomes ML, Freitas RS, Moreno S, Lima-Filho GL, Paula EF, Jales RLC, Bernardo-Filho M. Which are the most used radionuclides in the pet and in the spect techniques in the world? J Labelled Comp Radiopharm 2012. [DOI: 10.1002/jlcr.25804401295] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Abstract
Measurements of the magnetic susceptibility of the frustrated pyrochlore magnet Gd(2)Sn(2)O(7) have been performed at temperatures below T = 5 K and in magnetic fields up to H = 12 T. The phase boundaries determined from these measurements are mapped out in an H-T phase diagram. In this gadolinium compound, where the crystal-field splitting is small and the exchange and dipolar energy are comparable, the Zeeman energy overcomes these competing energies, resulting in at least four magnetic phase transitions below 1 K. These data are compared against those for Gd(2)Ti(2)O(7) and will, we hope, stimulate further studies.
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Affiliation(s)
- R S Freitas
- Instituto de Física, Universidade de São Paulo, CP 66318, 05314-970 São Paulo, SP, Brazil.
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Elmassalami M, Moreno R, Takeya H, Ouladdiaf B, Lynn JW, Freitas RS. Magnetic structures of quaternary intermetallic borocarbides RCo(2)B(2)C (R = Dy, Ho, Er). J Phys Condens Matter 2009; 21:436006. [PMID: 21832452 DOI: 10.1088/0953-8984/21/43/436006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The magnetic structures of the title compounds have been studied by neutron diffraction. In contrast to the isomorphous RNi(2)B(2)C compounds, wherein a variety of exotic incommensurate modulated structures has been observed, the magnetic structure of ErCo(2)B(2)C is found to be a collinear antiferromagnet with [Formula: see text] while those of HoCo(2)B(2)C and DyCo(2)B(2)C are observed to be simple ferromagnets. For all studied compounds, the moments are found to be confined within the basal plane and their magnitudes are comparable to the values obtained from the low-temperature isothermal magnetization measurements. The absence of modulated magnetic structures in the RCo(2)B(2)C series (for ErCo(2)B(2)C, verified down to 50 mK) is attributed to the quenching of the Fermi surface nesting features.
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Affiliation(s)
- M Elmassalami
- Instituto de Fisica, Universidade Federal do Rio de Janeiro, Caixa Postal 68528, 21945-970 Rio de Janeiro, Brazil
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Freitas RS, Carvalho-Vivi JO, Zamboni IM, Assis CM, Costa-Martins JE, Vicentini-Moreira AP. The importance of serological assays in diagnosing acute pulmonary histoplasmosis. J Venom Anim Toxins Incl Trop Dis 2009. [DOI: 10.1590/s1678-91992009000200010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Ke X, Freitas RS, Ueland BG, Lau GC, Dahlberg ML, Cava RJ, Moessner R, Schiffer P. Nonmonotonic zero-point entropy in diluted spin ice. Phys Rev Lett 2007; 99:137203. [PMID: 17930629 DOI: 10.1103/physrevlett.99.137203] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2007] [Indexed: 05/25/2023]
Abstract
Water ice and spin ice are important model systems in which theory can directly account for "zero-point" entropy associated with quenched configurational disorder. Spin ice differs from water ice in the important respect that its fundamental constituents, the spins of the magnetic ions, can be removed through replacement with nonmagnetic ions while keeping the lattice structure intact. In order to investigate the interplay of frustrated interactions and quenched disorder, we have performed systematic heat capacity measurements on spin ice materials which have been thus diluted up to 90%. Investigations of both Ho and Dy spin ices reveal that the zero-point entropy depends nonmonotonically on dilution and approaches the value of Rln2 in the limit of high dilution. The data are in good agreement with a generalization of Pauling's theory for the entropy of ice.
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Affiliation(s)
- X Ke
- Department of Physics and Materials Research Institute, Pennsylvania State University, University Park, Pennsylvania 16802, USA
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Freitas RS, Moreno SRF, Lima-Filho GL, Fonseca AS, Bernardo-Filho M. Effect of a commercial extract of Paullinia cupana (guarana) on the binding of 99mTc-DMSA on blood constituents: An in vivo study. Appl Radiat Isot 2007; 65:528-33. [PMID: 17350271 DOI: 10.1016/j.apradiso.2007.01.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2006] [Accepted: 01/11/2007] [Indexed: 11/21/2022]
Abstract
We studied the influence of a commercial extract of Paullinia cupana (guarana) on the binding of technetium-99m-dimercaptosuccinic acid ((99m)Tc-DMSA) on blood constituents. Plasma (P) and blood cells (BC) from Wistar rats (control and treated) were separated. P and BC were precipitated with trichloroacetic acid (TCA) or ammonium sulphate (AS) and soluble (SF) and insoluble fractions (IF) isolated. The percentage of incorporated radioactivity (%ATI) in each fraction was determined. The treatment influenced the %ATI in IF-P and in IF-BC isolated by TCA precipitation.
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Affiliation(s)
- R S Freitas
- Departamento de Biofísica e Biometria, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, Avenida 28 de Setembro, 87 Fundos, 4 Andar, Rio de Janeiro 20551-030, Brazil
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Wang RF, Nisoli C, Freitas RS, Li J, McConville W, Cooley BJ, Lund MS, Samarth N, Leighton C, Crespi VH, Schiffer P. Artificial ‘spin ice’ in a geometrically frustrated lattice of nanoscale ferromagnetic islands. Nature 2006; 439:303-6. [PMID: 16421565 DOI: 10.1038/nature04447] [Citation(s) in RCA: 653] [Impact Index Per Article: 36.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2005] [Accepted: 11/16/2005] [Indexed: 11/08/2022]
Abstract
Frustration, defined as a competition between interactions such that not all of them can be satisfied, is important in systems ranging from neural networks to structural glasses. Geometrical frustration, which arises from the topology of a well-ordered structure rather than from disorder, has recently become a topic of considerable interest. In particular, geometrical frustration among spins in magnetic materials can lead to exotic low-temperature states, including 'spin ice', in which the local moments mimic the frustration of hydrogen ion positions in frozen water. Here we report an artificial geometrically frustrated magnet based on an array of lithographically fabricated single-domain ferromagnetic islands. The islands are arranged such that the dipole interactions create a two-dimensional analogue to spin ice. Images of the magnetic moments of individual elements in this correlated system allow us to study the local accommodation of frustration. We see both ice-like short-range correlations and an absence of long-range correlations, behaviour which is strikingly similar to the low-temperature state of spin ice. These results demonstrate that artificial frustrated magnets can provide an uncharted arena in which the physics of frustration can be directly visualized.
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Affiliation(s)
- R F Wang
- Department of Physics and Materials Research Institute, Pennsylvania State University, University Park, Pennsylvania 16802, USA
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Moreno SRF, Freitas RS, Rocha EK, Lima-Filho GL, Bernardo-Filho M. Protection of plasmid DNA by a Ginkgo biloba extract from the effects of stannous chloride and the action on the labeling of blood elements with technetium-99m. Braz J Med Biol Res 2004; 37:267-71. [PMID: 14762583 DOI: 10.1590/s0100-879x2004000200015] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Ginkgo biloba extract (EGb) is a phytotherapeutic agent used for the treatment of ischemic and neurological disorders. Because the action of this important extract is not fully known, assays using different biological systems need to be performed. Red blood cells (RBC) are labeled with technetium-99m (Tc-99m) and used in nuclear medicine. The labeling depends on a reducing agent, usually stannous chloride (SnCl2). We assessed the effect of different concentrations of EGb on the labeling of blood constituents with Tc-99m, as sodium pertechnetate (3.7 MBq), and on the mobility of a plasmid DNA treated with SnCl2 (1.2 microg/ml) at room temperature. Blood was incubated with EGb before the addition of SnCl2 and Tc-99m. Plasma (P) and RBC were separated and precipitated with trichloroacetic acid, and soluble (SF-P and SF-RBC) and insoluble (IF-P and IF-RBC) fractions were isolated. The plasmid was incubated with Egb, SnCl2 or EGb plus SnCl2 and agarose gel electrophoresis was performed. The gel was stained with ethidium bromide and the DNA bands were visualized by fluorescence in an ultraviolet transilluminator system. EGb decreased the labeling of RBC, IF-P and IF-RBC. The supercoiled form of the plasmid was modified by treatment with SnCl2 and protected by 40 mg/ml EGb. The effect of EGb on the tested systems may be due to its chelating action with the stannous ions and/or pertechnetate or to the capability to generate reactive oxygen species that could oxidize the stannous ion.
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Affiliation(s)
- S R F Moreno
- Departamento de Patologia, Universidade Federal Fluminense, Niterói, Rio de Janeiro, Brazil.
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Lima-Filho GL, Lima GMT, Freitas RS, Aleixo LCM, Moreno SRF, Catanho MTJA, Bernardo-Filho M. Evaluation of the phytic acid effect on the labeling of blood elements with technetium-99m and on the survival of a strain of Escherichia coli treated with stannous fluoride. Mol Cell Biochem 2003; 247:121-6. [PMID: 12841639 DOI: 10.1023/a:1024111006286] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The labeling of red blood cells with technetium-99m (99mTc) depends on a reducing agent and stannous ions, as chloride or fluoride, are widely utilized. This labeling may also be altered by drugs. Moreover, some authors have reported that the survival of Escherichia coli (E. coli) cultures decreases in presence of stannous ions. Phytic acid is present in the daily diet and we evaluated its influence on: (i) the labeling of blood elements with 99mTc and (ii) on the survival of an E. coli strain treated with stannous fluoride. Heparinized whole blood was withdrawn from Wistar rats and it was incubated with stannous chloride and with 99mTc, as sodium pertechnetate, centrifuged and plasma (P) and blood cells (BC) were isolated. Samples of P and BC were also precipitated with trichloroacetic acid, centrifuged and soluble (SF) and insoluble fractions (IF) isolated. E. coli culture was treated with stannous fluoride in presence of phytic acid. As phytic acid altered the fixation of 99mTc on BC, on IF-P and on IF-BC and, moreover, it abolished the lethal effect of stannous fluoride on the E. coli culture, we can suggest that, probably, phytic acid would have chelating properties to the stannous ions.
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Affiliation(s)
- G L Lima-Filho
- Departamento de Biofísica e Biometria, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
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Lima EAC, Diré G, Mattos DMM, Freitas RS, Gomes ML, de Oliveira MBN, Faria MVC, Jales RL, Bernardo-Filho M. Effect of an extract of cauliflower (leaf) on the labeling of blood elements with technetium-99m and on the survival of Escherichia coli AB1157 submitted to the treatment with stannous chloride. Food Chem Toxicol 2002; 40:919-23. [PMID: 12065213 DOI: 10.1016/s0278-6915(02)00065-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The labeling of red blood cells (RBC) with technetium-99m (99mTc) depends on a reducing agent and stannous chloride (SnCl(2)) and is widely utilized. This labeling may also be altered by drugs, and SnCl(2) reduces the survival of Escherichia coli cultures. Cauliflower (Brassica oleracea L. var. botrytis) is used in folk medicine and we evaluated its influence on (i) the labeling of blood elements with 99mTc, and (ii) on the survival of an E. coli strain. Blood was withdrawn from rats that drank the extract of cauliflower (15 days). Blood was incubated with SnCl(2) and with 99mTc, as sodium pertechnetate, centrifuged and plasma (P) and RBC were isolated. Samples of P and RBC were also precipitated, centrifuged and soluble and insoluble fractions isolated. E. coli culture was treated with SnCl(2) in the presence of cauliflower. The extract of cauliflower did not alter the fixation of 99mTc on blood fractions; however, it abolished the lethal effect of SnCl(2) on the E. coli culture. We suggest that the substances present in the extract of cauliflower probably, would have redox property with different mechanisms of action. The oxidant action of the substances of the extract would not be strong enough to oxidise the stannous ions altering the 99mTc-labeling. However, the referred substances could oxidise these ions sufficiently to protect the E. coli culture against the lethal effect of the stannous ion.
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Affiliation(s)
- E A C Lima
- Universidade do Estado do Rio de Janeiro, Instituto de Biologia Roberto Alcantara Gomes, Departamento de Biofísica e Biometria, Av. 28 de setembro, 87, Brazil
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Mir M, Guimarães RB, Fernandes JC, Continentino MA, Doriguetto AC, Mascarenhas YP, Ellena J, Castellano EE, Freitas RS, Ghivelder L. Structural transition and pair formation in Fe3O2BO3. Phys Rev Lett 2001; 87:147201. [PMID: 11580673 DOI: 10.1103/physrevlett.87.147201] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2001] [Indexed: 05/23/2023]
Abstract
We observe for the first time a structural phase transition in the oxyborate Fe3O2BO3 which occurs along three leg ladders present in this material. X-ray diffraction shows that this transition at 283 K is associated with a new phase where atomic displacements occur in alternate directions perpendicular to the axis and within the plane of the ladders. Magnetic data show that these displacements lead to the formation of singlet pairs which dissociate close to the structural transition. Anomalies in the transport properties also occur close to 283 K showing that the structural transition is related to a charge ordering phenomenon in a low dimensional structure.
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Affiliation(s)
- M Mir
- Instituto de Física, Universidade Federal Fluminense, Campus da Praia Vermelha, Niterói, 24.210-340, RJ, Brazil
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Mattos DM, Gomes ML, Freitas RS, Bernardo-Filho M. Model to evaluate the toxic effect of drugs: vincristine effect in the mass of organs and in the distribution of radiopharmaceuticals in mice. Mutat Res 2001; 496:137-43. [PMID: 11551489 DOI: 10.1016/s1383-5718(01)00224-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
There are evidences that the biodistribution of radiopharmaceuticals can be modified by some drugs. As chemotherapeutic drugs present important toxic effects, we studied the vincristine effect in the mass of organs and are trying to develop a model to evaluate the action of chemotherapeutic drug using the biodistribution of radiopharmaceuticals. Vincristine was administered (n=15) into female Balb/c mice, the organs isolated and their mass determined. To study the vincristine effect in the biodistribution of technetium-99m-dimercaptosuccinic acid (99mTc-DMSA) or technetium-99m-diethylenetriaminepentaacetic acid (99mTc-DTPA), vincristine (0.03 mg) was administered in the animals (n=15) in three doses. 99mTc-DMSA or 99mTc-DTPA was injected 1h after the last dose. After 0.5h, the animals were sacrificed and the percentage of radioactivity (%ATI) and the percentage of radioactivity per gram of tissue (%ATI/g) in each organ were calculated. The results have shown that the mass decreased significantly (Wilcoxon test, P<0.05) in thymus, spleen, ovary, uterus, kidneys, pancreas. The %ATI to 99mTc-DMSA increased in lung, pancreas, heart, thyroid, brain, and bone, and the %ATI/g increased in uterus, ovary, spleen, thymus, kidney, lung, liver, pancreas, heart, thyroid, brain and bone. To 99mTc-DTPA, the %ATI increased in uterus, ovary, spleen, thymus, kidney, lung, liver, stomach, heart and bone, and the %ATI/g increased in uterus, ovary, spleen, thymus, kidney, lung, liver, stomach, heart and bone. The results were statistically significant (Wilcoxon test). The results can be explained by the metabolization, therapeutic, toxicological or immunosupressive action of the vincristine. This model, probably, should be used to evaluate the toxic effect of various drugs.
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Affiliation(s)
- D M Mattos
- Departamento de Biofísica e Biometria, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, Av. 28 de setembro, 87, RJ 20551-030, Rio de Janeiro, Brazil.
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Gomes ML, Mattos DMM, Freitas RS, Moreno SRF, Bernardo-Filho M. Evaluation of the toxic effect of chemotherapeutic drugs: Study on the biodistribution of 99mTc-radiopharmaceuticals used in bone scintigraphy in mice. J Labelled Comp Radiopharm 2001. [DOI: 10.1002/jlcr.25804401219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Mattos DM, Gomes ML, Freitas RS, Boasquevisque EM, Cardoso VN, Paula EF, Bernardo-Filho M. The effect of vincristine on the biodistribution of technetium-99m DTPA, GHA, and DMSA in Balb/c female mice. J Nucl Med Technol 2000; 28:271-4. [PMID: 11142330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
OBJECTIVE Vincristine has been widely used in various chemotherapeutic protocols in oncology. The purpose of this study was to evaluate the effect of vincristine on the biodistribution of 99mTc-DMSA, 99mTc-GHA, and 99mTc-DTPA in Balb/c female mice. METHODS Vincristine (0.03 mg, 0.3 mL) was injected into female isogenic Balb/c mice (n = 15), in 3 doses over an interval of 96 h. The 99mTc-DMSA, 99mTc-GHA, or 99mTc-DTPA (7.4 MBq) was administered after the last dose of vincristine. After 0.5 h the animals were killed rapidly. The organs (pancreas, thyroid, brain, thymus, ovary, uterus, spleen, kidney, heart, stomach, lung, liver, bone, and lymph nodes) were isolated and the radioactivity in each organ was counted in a NaI(Tl) well counter. The percentage of radioactivity (%) in each was calculated and compared with the control group. Statistical analysis was performed by Wilcoxon test (P < 0.05). RESULTS The percentage of 99mTc-DMSA was increased in the lung, pancreas, heart, thyroid, brain, bone, and lymph nodes (inguinal and mesenteric). The percentage of 99mTc-GHA was decreased in the uterus, ovary, spleen, thymus, lymph nodes (inguinal and mesenteric), kidney, and heart. The percentage of 99mTc-DTPAwas increased in thymus, lymph nodes (inguinal and mesenteric), ovary, uterus, spleen, kidney, heart, stomach, lung, liver, and bone. CONCLUSION The results could be explained by the metabolization, toxic effect, therapeutic, or immunosupressive action of the studied chemotherapeutic drug.
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Affiliation(s)
- D M Mattos
- Instituto Nacional de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, Brasil
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Mattos DM, Gomes ML, Freitas RS, Rodrigues PC, Nascimento VD, Boasquevisque EM, Paula EF, Bernardo-Filho M. Assessment of the effect of vincristine on the biodistribution of 99Tcm-labelled glucoheptonic acid in female Balb/c mice. Nucl Med Commun 2000; 21:557-60. [PMID: 10894566 DOI: 10.1097/00006231-200006000-00010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
There is evidence that the biodistribution and the pharmacokinetics of 99Tcm radiopharmaceuticals can be modified by some drugs, pathological states, irradiation and surgical procedures. Vincristine have been widely used in various chemotherapeutic protocols in oncology. We are trying to develop an animal model to assess the toxicology in different organs of compounds used as therapeutic drugs. We have studied the effect of vincristine on the distribution of 99Tcm-glucoheptonic acid (99Tcm-GHA) in female mice. After the last dose of vincristine, 99Tcm-GHA (7.4 MBq) was injected, the animals sacrificed and the percentage of radioactivity determined in the isolated organs. The percentage of activity was significantly decreased in the uterus, ovary, spleen, thymus, lymph nodes (inguinal and mesenteric), kidney and heart, but was not significantly altered in the lung, liver, pancreas, stomach, thyroid, brain and bone. Our results can be explained by the metabolic, toxic, therapeutic and immunosuppressive actions of this chemotherapeutic drug.
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Affiliation(s)
- D M Mattos
- Universidade do Estado do Rio de Janeiro, Instituto de Biologia Roberto Alcântara Gomes, Departamento de Biofísica e Biometria, RJ, Brasil
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Freitas RS, Gomes ML, Mattos DMM, Bernardo-Filho M. Study of the binding of99mtechnetium-radiopharmaceuticals on blood cells and plasma proteins: evaluation using precipitation with trichloroacetic acid. J Labelled Comp Radiopharm 2000. [DOI: 10.1002/1099-1344(200006)43:7<663::aid-jlcr351>3.0.co;2-p] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Mattos DM, Gomes ML, Freitas RS, Rodrigues PC, Paula EF, Bernardo-Filho M. A model to evaluate the biological effect of natural products: vincristine action on the biodistribution of radiopharmaceuticals in BALB/c female mice. J Appl Toxicol 1999; 19:251-4. [PMID: 10439338 DOI: 10.1002/(sici)1099-1263(199907/08)19:4<251::aid-jat575>3.0.co;2-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Natural products have been widely used by human beings. However, sometimes the biological effects of these products are not fully known. We are trying to develop a model to evaluate the toxicity of compounds employed as therapeutic drugs. This model is based on the capability of natural products to alter the biodistribution of radiopharmaceuticals labelled with technetium-99m (99mTc). The acceptance of 99mTc-labelled radiopharmaceuticals is so rapid and its current use so diverse that it is not possible to study this radionuclide's behaviour in the body more deeply. There is evidence that the biodistribution or the pharmacokinetics of radiopharmaceuticals can be modified by some drugs, by pathological states, by irradiation and by surgical procedures. A lack of knowledge of such factors can induce a misvisualization of the scintigraphic images, leading to a misdiagnosis. Vincristine is a natural product that has been employed in various chemotherapeutic protocols in oncology. We have studied the effect of vincristine on the distribution of [99mTc]methylenediphosphonic acid ([99mTc]MDP) in female mice. After the last dose of vincristine, [99mTc]MDP was injected, the animals were sacrificed and the percentage of radioactivity (%ATI) was determined in the isolated organs. The %ATI was significantly decreased in the uterus, ovary, spleen, thymus, lymph nodes (inguinal and mesentheric), kidney, liver, pancreas, stomach, heart, brain and bone of the animals treated with the natural product. Several biological effects have been reported in patients treated with vincristine. These effects could justify the alterations in the uptake of the radiopharmaceutical in specific organs. Moreover, these results have shown that it is possible to employ this model to evaluate the toxicity of drugs.
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Affiliation(s)
- D M Mattos
- Instituto Nacional do Câncer, Centro de Pesquisa Básica, Rio de Janeiro, Brasil
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Freitas RS, Gutfilen B, da Fonseca LM, Bernardo-Filho M. Evaluation of 99mtechnetium-radiopharmaceutical binding to blood elements using different trichloroacetic acid concentrations. Yale J Biol Med 1996; 69:483-8. [PMID: 9436291 PMCID: PMC2589038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Secure determination of the binding of 99mTc-radiopharmaceuticals to plasma (P) and blood cell (BC) constituents can help to understand the biodistribution of radiophamaceuticals. The reported precipitation studies of blood with radiopharmaceuticals have shown that the results can not be easily compared between studies. We decided to determine the "gold standard" concentration of trichloroacetic acid (TCA) to evaluate the binding to blood elements for several radiopharmaceuticals used in routine nuclear medicine. We have studied phytic (99mTc-PHY), diethylenetriaminepentaacetic (99mTc-DTPA), glucoheptonic (99mTc-GHA) and dimercaptosuccinic (99mTc-DMSA) acids. Blood was incubated with radiopharmaceuticals, centrifuged and P and BC separated. Samples of P and BC were also precipitated with TCA concentrations (20.0, 10.0, 5.0, 1.0, 0.5 and 0.1 percent) and soluble (SF) and insoluble fractions (IF) were isolated. The percent radioactivity (percent rad) in IF-P depends on TCA concentration. It varied from 36.4 to 65.0 (99mTc-PHY), from 17.9 to 32.0 (99mTc-DTPA), from 11.5 to 38.8 (99mTc-GHA) and from 52.8 to 66.2 (99mTc-DMSA). The results for the binding of 99mTc-PHY to IF-P show that there was no differences in the percent rad when TCA concentrations of 0.1 to 1.0 percent were used. For 99mTc-DTPA, 5.0 percent is the best TCA concentration. For 99mTc-GHA, low values of percent rad bound to IF-P is found with TCA concentrations of 0.1, 0.5 and 1.0. Interestingly, with 99mTc-DMSA, high values of bound radioactivity are not dependent on TCA concentrations (0.1 to 10.0). Radioactivity in IF-BC depends on TCA concentration and it varied for 99mTc-PHY (80.1 to 54.1) and for 99mTc-GHA (85.5 to 61.7). With 99mTc-DTPA and with 99mTc-DMSA the percent rad in IF-BC seems independent of TCA concentration. We suggest that the evaluation of the binding of the various 99mTc-radiopharmaceuticals to blood constituents, using only one TCA concentration, should be avoided.
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Affiliation(s)
- R S Freitas
- Centro de Pesquisa Básica, Instituto Nacional de Câncer, Rio de Janeiro, Brasil
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