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Abstract
Goiters tend to grow slowly and steadily over many years, occasionally reaching the mediastinum and extending through the thoracic inlet into the visceral compartment. In most cases, retrosternal goiters originate from the cervical portion of the thyroid. The incidence of retrosternal goiters varies considerably, ranging from 0.2 to 45% of all thyroidectomies, depending on the criteria used to define this type of goiter. Symptoms are generally related to the compressive nature of the mass on the adjacent structures, and most patients report some form of respiratory manifestation associated with the goiter. A diagnostic assessment usually includes an evaluation of thyroid function, chest radiography, and computed tomography. Fine-needle aspiration biopsy should be avoided in substernal areas of the goiter due to limited visibility and location of vital structures in this region. Treatment of retrosternal goiters is surgical, as medical therapy is generally unsuccessful in these cases.
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Affiliation(s)
- M Knobel
- Thyroid Unit, Division of Endocrinology and Metabolism, Hospital das Clínicas, School of Medicine, Universidade de São Paulo, Av. Dr. Eneas de Carvalho Aguiar, 155, 8th floor, bl 3, PAMb, São Paulo, 05403-900, Brazil.
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2
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Abstract
Goiter, an enlargement of the thyroid gland, is a common problem in clinical practice associated with iodine deficiency, increase in serum thyroid-stimulating hormone (TSH) level, natural goitrogens, smoking, and lack of selenium and iron. Evidence suggests that heredity also has an important role in the etiology of goiter. The current classification divides goiter into diffuse and nodular, which may be further subdivided into toxic (associated with symptoms of hyperthyroidism, suppressed TSH or both), or nontoxic (associated with a normal TSH level). Nodular thyroid disease with the presence of single or multiple nodules requires evaluation due to the risk of malignancy, toxicity, and local compressive symptoms. Measurement of TSH, accurate imaging with high-resolution ultrasonography or computed tomography, and fine-needle aspiration biopsy are the appropriate methods for evaluation and management of goiter. This review discusses the clinical presentation, diagnostic evaluation, and treatment considerations of nontoxic diffuse and nodular goiters.
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Affiliation(s)
- M Knobel
- Thyroid Unit, Division of Endocrinology and Metabolism, Hospital das Clínicas, University of São Paulo Medical School, Av. Dr. Enéas de Carvalho Aguiar, 155 - 8th floor, bl 3, PAMB, São Paulo, 05403-900, Brazil.
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Sarveena S, Muraca D, Zélis PM, Javed Y, Ahmad N, Vargas JM, Moscoso-Londoño O, Knobel M, Singh M, Sharma SK. Surface and interface interplay on the oxidizing temperature of iron oxide and Au–iron oxide core–shell nanoparticles. RSC Adv 2016. [DOI: 10.1039/c6ra15610j] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Formation of core and shell shape through tuning the reaction time as well as the oxidizing temperatures. Spherical–spherical and spherical triangular shaped core–shell structures have been obtained at an optimum oxidation temperature of 150 °C.
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Affiliation(s)
| | - Diego Muraca
- Instituto de Física Gleb Wataghin
- Universidade Estadual de Campinas (UNICAMP)
- Brazil
- Centro de Ciencias Naturais e Humanas
- Universidade Federal do ABC-UFABC
| | - P. Mendoza Zélis
- Instituto de Física de La Plata (IFLP-CONICET)
- Departamento de Física
- Facultad de Ciencias Exactas
- Universidad Nacional de La Plata (UNLP)
- 1900 La Plata
| | - Y. Javed
- Department of Physics
- University of Agriculture
- Faisalabad
- Pakistan
| | - N. Ahmad
- Laboratoire Matériaux et Phénomènes Quantiques
- UMR 7162 CNRS/Université Paris Diderot
- Paris F-75205 Cedex 13
- France
| | - J. M. Vargas
- Centro Atomico Bariloche (CNEA)
- Instituto Balseiro (U. N. Cuyo) and Conicet
- 8400 San Carlos de Bariloche
- Argentina
| | - O. Moscoso-Londoño
- Instituto de Física Gleb Wataghin
- Universidade Estadual de Campinas (UNICAMP)
- Brazil
| | - M. Knobel
- Instituto de Física Gleb Wataghin
- Universidade Estadual de Campinas (UNICAMP)
- Brazil
- Laboratório Nacional de Nanotecnologia (LNNano/CNPEM)
- Campinas-SP
| | - M. Singh
- Department of Physics
- H. P. University
- Shimla
- India
| | - S. K. Sharma
- Departamento de Física
- Universidade Federal do Maranhão
- 65085-580 São Luis
- Brazil
- Department of Physics
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de Farias CR, Cardoso BR, de Oliveira GMB, de Mello Guazzelli IC, Catarino RM, Chammas MC, Cozzolino SMF, Knobel M. A randomized-controlled, double-blind study of the impact of selenium supplementation on thyroid autoimmunity and inflammation with focus on the GPx1 genotypes. J Endocrinol Invest 2015; 38:1065-74. [PMID: 25894865 DOI: 10.1007/s40618-015-0285-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 04/01/2015] [Indexed: 10/23/2022]
Abstract
PURPOSE To analyze the impact of selenium supplementation on serum antiTPO levels and thyroid echogenicity in patients with CAT, evaluating the response in subgroups with different GPx1 genotypes. METHODS CAT patients (n = 55) with positive antiTPO were randomized to selenomethionine (SeMet) 200 μg daily (n = 28) or placebo (n = 27) for 3 months. Assessments included GPx1 genotyping at baseline and serum levels of plasma selenium, erythrocyte GPx1 activity, antiTPO and thyroid echogenicity at baseline, and 3 and 6 months. RESULTS In the SeMet group, the increase in plasma levels of selenium and erythrocyte GPx1 activity was similar among patients with different GPx1 genotypes. In the overall cohort, patients randomized to SeMet showed a 5 % decrease in antiTPO levels at 3 months (p = non-significant) and 20 % at 6 months (p < 0.001 versus 3 months). In contrast, patients in the placebo group did not show significant changes in antiTPO levels at any time point. Subgroup analysis showed that patients with different GPx1 genotypes presented comparable responses in antiTPO levels and echogenicity index to SeMet. CONCLUSIONS Selenium supplementation decreased serum antiTPO levels in CAT patients, with similar response among patients with different GPx1 genotypes.
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Affiliation(s)
- C R de Farias
- Thyroid Unit and Laboratory of Cellular and Molecular Biology (LIM-25), Division of Endocrinology and Metabolism, University of São Paulo Medical School, Hospital das Clínicas, Av. Dr. Enéas de Carvalho Aguiar, 155, 8th floor, bl 3, PAMB, São Paulo, SP, 05403-900, Brazil.
| | - B R Cardoso
- Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Science, University of São Paulo, Av. Prof. Lineu Prestes 580, bl 14, Cidade Universitária, São Paulo, SP, 05508-000, Brazil.
| | - G M B de Oliveira
- Ultrasound Unit, Department of Radiology, University of São Paulo Medical School, Hospital das Clínicas, Av Dr Enéas de Carvalho Aguiar, 255, 3rd floor, Unit 013, São Paulo, SP, 05403-900, Brazil.
| | - I C de Mello Guazzelli
- Laboratory of Cellular and Molecular Endocrinology, LIM-25, Division of Endocrinology and Metabolism, University of São Paulo Medical School, Av. Dr. Arnaldo 455, 4th floor, Units 4305/4307, São Paulo, SP, 01246-903, Brazil.
| | - R M Catarino
- Hematology and Biochemistry, Center of Pathology, Adolpho Lutz Institute, Av. Dr. Arnaldo 351, 7th floor, São Paulo, SP, 01246-000, Brazil.
| | - M C Chammas
- Ultrasound Unit, Department of Radiology, University of São Paulo Medical School, Hospital das Clínicas, Av. Dr. Enéas de Carvalho Aguiar, 255, 3rd floor, Unit 013, São Paulo, SP, 05403-010, Brazil.
| | - S M F Cozzolino
- Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Science, University of São Paulo, Av. Prof. Lineu Prestes 580, bl 14, Cidade Universitária, São Paulo, SP, 05508-000, Brazil.
| | - M Knobel
- Thyroid Unit and Laboratory of Cellular and Molecular Biology (LIM-25), Division of Endocrinology and Metabolism, University of São Paulo Medical School, Hospital das Clínicas, Av. Dr. Enéas de Carvalho Aguiar, 155, 8th floor, bl 3, PAMB, São Paulo, SP, 05403-900, Brazil.
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Yu RH, Zhang XX, Tejada J, Knobel M, Tiberto P, Allia P, Vinai F. Improved giant magnetoresistance in magnetic granular Co5 Cu95 alloys by direct-current joule heating. ACTA ACUST UNITED AC 2014. [DOI: 10.1007/s002570050023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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González M, Lemus-Santana A, Rodríguez-Hernández J, Aguirre-Velez C, Knobel M, Reguera E. Intermolecular interactions between imidazole derivatives intercalated in layered solids. Substituent group effect. J SOLID STATE CHEM 2013. [DOI: 10.1016/j.jssc.2013.05.029] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Lemus-Santana AA, González M, Rodríguez-Hernández J, Knobel M, Reguera E. 1-Methyl-2-Pyrrolidone: From Exfoliating Solvent to a Paramagnetic Ligand. J Phys Chem A 2013; 117:2400-7. [DOI: 10.1021/jp4007813] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- A. A. Lemus-Santana
- Centro de Investigación
en Ciencia Aplicada y Tecnología Avanzada, Unidad Legaria, Instituto Politécnico Nacional, México
| | - M. González
- Centro de Investigación
en Ciencia Aplicada y Tecnología Avanzada, Unidad Legaria, Instituto Politécnico Nacional, México
| | - J. Rodríguez-Hernández
- Centro de Investigación
en Ciencia Aplicada y Tecnología Avanzada, Unidad Legaria, Instituto Politécnico Nacional, México
- Instituto de Ciencia y Tecnología
de Materiales, Universidad de La Habana, Cuba
| | - M. Knobel
- Instituto deFísica
“GlebWataghin”, Universidade Estadual de Campinas, SP, Brazil
| | - E. Reguera
- Centro de Investigación
en Ciencia Aplicada y Tecnología Avanzada, Unidad Legaria, Instituto Politécnico Nacional, México
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Kumar S, Kim GW, Koo BH, Sharma SK, Knobel M, Chung H, Lee CG. Structural and magnetic study of a diluted magnetic semiconductor: Fe-doped CeO2 nanoparticles. J Nanosci Nanotechnol 2011; 11:555-559. [PMID: 21446496 DOI: 10.1166/jnn.2011.3176] [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] [Indexed: 05/30/2023]
Abstract
This paper reports the effect of Fe doping on the structure and room temperature ferromagnetism of CeO2 nanoparticles. X-ray diffraction and the selective area electron diffraction measurements performed on the Ce(1-x)Fe(x)O2 (0 < or = x < or = 0.07) nanoparticles showed a single-phase nature with a cubic structure, and none of the samples showed the presence of any secondary phase. The mean particle size, which was calculated using transmission electron microscopy, increased with the increase in the Fe content. The DC magnetization measurements that were performed at room temperature showed that all the samples exhibited ferromagnetism. The saturation magnetic moment increased with the increase in the Fe content.
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Affiliation(s)
- Shalendra Kumar
- School of Nano and Advanced Materials Engineering, Changwon National University, 9 Sarim-Dong, Changwon 641-773, Republic of Korea
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Bain P, Knobel M, Gontu V, Baja NPS. POMD13 Distinguishing tremor-dominant Parkinson's disease from tremulous subjects without evidence of dopaminergic deficit by spirography: an FP-CIT validated study. J Neurol Psychiatry 2010. [DOI: 10.1136/jnnp.2010.226340.173] [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: 11/04/2022]
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10
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Sharma SK, Vargas JM, De Biasi E, Béron F, Knobel M, Pirota KR, Meneses CT, Kumar S, Lee CG, Pagliuso PG, Rettori C. The nature and enhancement of magnetic surface contribution in model NiO nanoparticles. Nanotechnology 2010; 21:035602. [PMID: 19966407 DOI: 10.1088/0957-4484/21/3/035602] [Citation(s) in RCA: 5] [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] [Indexed: 05/28/2023]
Abstract
We report an alternative synthesis method and novel magnetic properties of Ni-oxide nanoparticles (NPs). The NPs were prepared by thermal decomposition of nickel phosphine complexes in a high-boiling-point organic solvent. These particles exhibit an interesting morphology constituted by a crystalline core and a broad disordered superficial shell. Our results suggest that the magnetic behavior is mainly dominated by strong surface effects at low temperature, which become evident through the observation of shifted hysteresis loops (approximately 2.2 kOe), coercivity enhancement (approximately 10.2 kOe) and high field irreversibility (>or=50 kOe). Both an exchange bias and a vertical shift in magnetization can be observed in this system below 35 K after field cooling. Additionally, the exchange bias field shows a linear dependence on the magnetization shift values, which elucidate the role of pinned spins on the exchange fields. The experimental data are analyzed in terms of the interplay between the interface exchange coupling and the antiferromagnetically ordered structure of the core.
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Affiliation(s)
- S K Sharma
- Instituto de Fisica Gleb Wataghin, Universidade Estadual de Campinas (UNICAMP) Campinas, SP, Brazil.
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11
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Drager LF, Balsanalli AP, Busch EL, Knobel M, Macedo RCR, Moura DF, Nanami R, Santos OFP. High risk for obstructive sleep apnea in patients with acute coronary syndrome: initial experience from a coronary unit. Crit Care 2009. [PMCID: PMC4085435 DOI: 10.1186/cc7837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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12
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Zhukov A, García C, Del Val JJ, Gonzalez J, Knobel M, Serantes D, Baldomir D, Zhukova V. Studies of Fe-Cu microwires with nanogranular structure. J Phys Condens Matter 2009; 21:035301. [PMID: 21817277 DOI: 10.1088/0953-8984/21/3/035301] [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
We report on the fabrication, and structural and magnetic characterization of Cu(63)Fe(37) microwires with granular structure produced by rapid quenching, using the Tailor-Ulitovsky method, from the immiscible alloys. X-ray diffraction study demonstrated that the structure consists of small (6-45 nm) crystallites of Cu and body centred cubic α-Fe. Magnetic properties have been measured in the range of 5-300 K using a SQUID (superconducting quantum interference device) magnetometer. The temperature dependences of the magnetization measured in a cooling regime when no external magnetic field is applied (zero-field cooling) and in the presence of the field (field cooling) show considerable difference below 20 K. This difference could be related to the presence of small α-Fe grains embedded in the Cu matrix. Those α-Fe grains appear to be blocked at temperatures below that at which the maximum of the magnetization is observed in the low temperature range. Significant magnetoresistance (about 7%) has been found in the samples studied. The shape of the observed dependences is typical of a giant magnetoresistance effect.
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Affiliation(s)
- A Zhukov
- Department of Materials Physics, Faculty of Chemistry, PO Box 1072, 20080 San Sebastian, Spain. TAMAG Ibérica SL, Parque Tecnológico de Miramón, Paseo Mikeletegi 56, 1a Planta, 20009 San Sebastián, Spain
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13
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Sharma SK, Kumar R, Kumar S, Knobel M, Meneses CT, Siva Kumar VV, Reddy VR, Singh M, Lee CG. Role of interparticle interactions on the magnetic behavior of Mg(0.95)Mn(0.05)Fe(2)O(4) ferrite nanoparticles. J Phys Condens Matter 2008; 20:235214. [PMID: 21694305 DOI: 10.1088/0953-8984/20/23/235214] [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] [Indexed: 05/30/2023]
Abstract
We present here a detailed investigation of the static and dynamic magnetic behavior of a Mg(0.95)Mn(0.05)Fe(2)O(4) spinel ferrite nanoparticle system synthesized by high-energy ball milling of almost identical particle size distributions ([Formula: see text], 5.1 and 6.0 ± 0.6 nm). The samples were characterized by using x-ray diffraction, Mössbauer spectroscopy, dc magnetization and frequency dependent real χ(')(T) and imaginary χ('')(T) parts of ac susceptibility measurements. The zero-field-cooled (ZFC) and field-cooled (FC) magnetization have been recorded in a low field and show a behavior typical of superparamagnetic particles above a temperature of 185 ± 5 K, which is further supported from the temperature dependent Mössbauer measurements. The fact that the blocking temperature calculated from the ZFC magnetization and Mössbauer data are almost similar gives a clear indication of the interparticle interactions among these nanoparticle systems. This is further supported from the FC magnetization curves, which are almost flat below a certain temperature (less than the blocking temperature), as compared with the monotonically increasing behavior characteristics of non-interacting superparamagnetic particles. A shift of the blocking temperature with increasing frequency was observed in the real χ(')(T) and imaginary χ('')(T) parts of the ac susceptibility measurements. The analysis of the results shows that the data fit well with the Vogel-Fulcher law, whereas trials using the Neel-Brown and power law are unproductive. The role of magnetic interparticle interactions on the magnetic behavior, namely superparamagnetic relaxation time and magnetic anisotropy, are discussed.
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Affiliation(s)
- S K Sharma
- Instituto de Fisica Gleb Wataghin, Universidade Estadual de Campinas (UNICAMP) Campinas, 13.083-970, SP, Brazil
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Knobel M, Nunes WC, Socolovsky LM, De Biasi E, Vargas JM, Denardin JC. Superparamagnetism and other magnetic features in granular materials: a review on ideal and real systems. J Nanosci Nanotechnol 2008; 8:2836-2857. [PMID: 18681019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
An overview on magnetic of nanostructured magnetic materials is presented, with particular emphasis on the basic features displayed by granular nanomagnetic solids. Besides a review of the basic concepts and experimental techniques, the role of structural disorder (mainly the distribution of grain sizes), interparticle magnetic interactions and surface effects are also discussed with some detail. Recent results, models and trends on the area are also discussed.
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Affiliation(s)
- M Knobel
- Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas CP 6165, 13083-970 Campinas (SP), Brazil
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15
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Vargas JM, Lima E, Socolovsky LM, Knobel M, Zanchet D, Zysler RD. Annealing effects on 5 nm iron oxide nanoparticles. J Nanosci Nanotechnol 2007; 7:3313-3317. [PMID: 18019166 DOI: 10.1166/jnn.2007.688] [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] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Morphological, structural and magnetic properties of 4.8 nm iron oxide nanoparticles have been investigated after annealing under inert atmosphere at different temperatures. The as-prepared iron oxide nanoparticles have been synthesized by chemical route from high temperature reaction of Fe(acac)3 solution in presence of oleic acid and oleylamine surfactant. Annealing the particles at low temperatures (Tann = 573 K) produces an increment of the mean size from 4.8 nm to 6.0 nm, preserving the same morphology. The coercive field of the annealed sample has a small increasing with respect to the as-prepared sample in agreement with the mean particle volume change. Annealing at higher temperature (Tann = 823 K) leads to a bimodal size distribution of the iron oxide nanoparticles with 6.0 nm and 17 nm mean sizes respectively, where the bigger particles dominate the observed magnetic properties.
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Affiliation(s)
- J M Vargas
- Centro Atómico Bariloche and Comisión Nacional de Energía Atómica, 8400 San Carlos de Bariloche, Rio Negro, Argentina
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Rubio IGS, Silva MNC, Knobel M, Romão R, Possato R, Gebrin EMMS, Buchpiguel C, Medeiros-Neto G. Peripheral blood levels of thyroglobulin mRNA and serum thyroglobulin concentrations after radioiodine ablation of multinodular goiter with or without pre-treatment with recombinant human thyrotropin. J Endocrinol Invest 2007; 30:535-40. [PMID: 17848834 DOI: 10.1007/bf03346345] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
We investigated the effect of therapeutic doses of radioiodine (RAI) on peripheral serum messenger thyroglobulin RNA (Tg mRNA) and serum thyroglobulin (sTg) in patients with multinodular goiter (MNG) preceded or not by treatment with recombinant human TSH (rhTSH). Fourteen patients with large MNG (91-542 ml) received RAI (550-2960 MBq). Half of the patients received 0.45 mg of rhTSH prior to the treatment (RAI+rhTSH group) and half did not (RAI group). Patients' blood samples were collected before and 24, 48, and 72 h; 7 and 30 days; and 6, 9, and 12 months after RAI treatment. Serum Tg was measured by immunoradiometric assay, serum anti-Tg by radioimmunoassay, and quantification of circulating Tg mRNA was performed by real-time PCR. The shrinkage of MNG volume was documented by serial computed tomography (CT) scans before, 6 and 12 months after RAI. Peak Tg mRNA and sTg were reached earlier in the RAI+rhTSH group (24 h and 48 h) than in the RAI group (7 days). Both declined after the peak and the lowest levels were observed at 12 months. The mean reduction of the thyroid volume was 19.8% (RAI group) and 30.3% (RAI+rhTSH group) at 6 months (ns) and 32.8% RAI and 52.5% (RAI+rhTSH group) at 12 months (p<0.05). After RAI treatment there was a significant and positive correlation between goiter volume and sTg only in the RAI group (r=0.7; p=0.032). Serum anti-Tg had a transitory and relatively small elevation in 3 and 2 patients, respectively, in the RAI and RAI+rhTSH groups. We concluded that after RAI ablation of MNG there is a rapid release of Tg into the serum possibly from the colloid, which is followed by an elevation of serum Tg mRNA that may be due to an increased release of follicular cells into the blood stream. Both phenomena are enhanced by the use of rhTSH before RAI treatment as a consequence of a more effective and prolonged radiation exposure of the thyroid follicles.
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Affiliation(s)
- I G S Rubio
- Thyroid Unit (LIM-25), Division of Endocrinology, Department of Medicine, University of São Paulo Medical School, São Paulo, Brazil
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Tavares T, Forlenza LMA, Correa AG, Mello AP, Borges GC, Brito DS, Dias KCR, Endrigo KALD, Makdisse MRP, Brito FS, Gomes IM, Knobel M. Impact of a new triage tool for screening acute myocardial infarction patients on the door-to-electrocardiogram time in an emergency department. Crit Care 2007. [PMCID: PMC3301174 DOI: 10.1186/cc5834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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18
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Figueiredo EJDA, Perez A, Knobel E, Souza JMA, Ferri MB, Knobel M, Nigri M, Silveira P, Morsch RD, Passos RH. Relationship between B-type natriuretic peptide plasma levels and echocardiography parameters in compensated chronic heart failure patients treated with levosimendan. Crit Care 2007. [PMCID: PMC3301175 DOI: 10.1186/cc5835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Makdisse MRP, Correa AG, Pfeferman A, Forlenza LMA, Knobel M, Mello AP, Tavares T, Oliveira V, Ellovitch S, Filho COB, Pieri A, Knobel E. Women with acute myocardial infarction are more likely than men to have a delayed door-to-electrocardiogram time. Crit Care 2007. [PMCID: PMC3301171 DOI: 10.1186/cc5831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Abstract
The thermal-induced changes in molecular magnets based on Prussian blue analogues, M(3)[Fe(CN)(6)](2).xH(2)O (M = Mn, Co, Ni, Cu, Zn, and Cd), were studied from infrared, X-ray diffraction, thermo-gravimetric, Mössbauer, and magnetic data. Upon being heated, these materials loose the crystalline water that enhances the interaction between the metal centers, as has been detected from Mössbauer spectroscopy data. At higher temperatures, a progressive decomposition process takes place, liberating CN(-) groups, which reduces the iron atom from Fe(III) to Fe(II) to form hexacyanoferrates(II). The exception corresponds to the cobalt compound that undergoes an inner charge transfer to form Co(III) hexacyanoferrate(II). In the case of zinc ferricyanide, the thermal decomposition is preceded by a structural transformation, from cubic to hexagonal. For M = Co, Ni, Cu, and Zn the intermediate reaction product corresponds to a solid solution of M(II) ferricyanide and ferrocyanide. For M = Mn and Cd the formation of a solid solution on heating was not detected. The crystal frameworks of the initial M(II) ferricyanide and of the formed M(II) ferrocyanide are quite different. In annealed Mn(II) ferricyanide samples, an increasing anti-ferromagnetic contribution on heating, which dominates on the initial ferrimagnetic order, was observed. Such a contribution was attributed to neighboring Mn(II) ions linked by aquo bridges. In the anhydrous annealed sample such interaction disappears. This effect was also studied in pure Mn(II) ferrocyanide. The occurrence of linkage isomerism and also the formation of Ni(III), Cu(III), and Zn(III) hexacyanoferrates(II) were discarded from the obtained experimental evidence.
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Affiliation(s)
- R Martínez-Garcia
- Institute of Science and Technology of Materials, San Lazaro and L, 10400 Havana, Cuba
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Ferri M, Passos R, Knobel M, Nigri M, Figueiredo E, Morsch R, Silveira P, Souza J, Perez A. Crit Care 2006; 10:P190. [DOI: 10.1186/cc4537] [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] Open
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Nigri M, Knobel M, Perez A, Erlichman M, Nussbacher A, Sousa J, Knobel E. Crit Care 2005; 9:P16. [DOI: 10.1186/cc3560] [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] Open
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Nigri M, Knobel M, Sousa J, Perez A, Erlichman M, Knobel E. Crit Care 2005; 9:P26. [DOI: 10.1186/cc3570] [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] Open
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Lima N, Cavaliere H, Tomimori E, Knobel M, Medeiros-Neto G. Prognostic value of serial serum thyroglobulin determinations after total thyroidectomy for differentiated thyroid cancer. J Endocrinol Invest 2002; 25:110-5. [PMID: 11929080 DOI: 10.1007/bf03343973] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Serial weekly serum samples (for 3 weeks) were obtained from 42 patients with differentiated thyroid cancer (DTC, papillary no.=35, follicular no.=6, Hurthle cell no.=1) for serum thyroid hormone, TSH and TG before and after total thyroidectomy. Serum specimens were also obtained one month after radioiodine (131I) therapy followed by suppressive dose of L-thyroxine (L-T4, 2.5 microg/kg). The patients were subdivided into four groups: group I: the DTC was confined to a single solid nodule (no.=1 2); group II: thyroid malignancy invaded local cervical structures but there were no lymph node metastases (no.=8); group III: DTC with lymph node metastases (no.=6); and group IV: DTC with distant metastases (no.=16). In all group I patients serum TG remained undetectable in spite of elevated serum TSH levels at the 3rd week post-surgery (PS). Only one of group II patients had a detectable serum TG value of 5.2 ng/ml (3rd week PS). By contrast, 37.5% of group III patients had detectable serum TG levels, ranging from 3.4 to 16.8 ng/ml (3rd week PS). Lymph node metastases were detected in 5 of these patients by whole body scan (WBS) and removed surgically in 3. As expected, group IV patients had elevated serum TG values ranging 33.0-958.0 ng/ml and distant metastases were confirmed in all of them by WBS. From the calculations through univariate logistic regression comparing TG concentrations at the 3rd week PS from groups I and II vs groups III and IV, we obtained a cut-off value of 2.3 ng/ml with the following efficacy features: sensitivity=74.5%; specificity=95%; positive predictive value=92.3%; negative predictive value=65.5%; and accuracy=73.8%. After 131I and L-T4 suppressive therapy, only 5 out of 36 patients of groups I, II and III had detectable serum TG levels (3.1-7.0 ng/ml) whereas serum TG was detectable in all group IV patients (ranging 2.5-8.6 ng/ml). We concluded that serum TG concentrations above 2.3 ng/ml at the 3rd week PS could be suggestive of lymph node or distant metastases in patients with DTC. Patients with serum TG above this limit could be considered at risk for metastatic disease and higher doses of diagnostic iodine-131 (131I) may be indicated for actinic ablation.
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MESH Headings
- Adenocarcinoma, Follicular/blood
- Adenocarcinoma, Follicular/surgery
- Adenocarcinoma, Follicular/therapy
- Adenoma, Oxyphilic/blood
- Adenoma, Oxyphilic/surgery
- Adenoma, Oxyphilic/therapy
- Adult
- Aged
- Aged, 80 and over
- Carcinoma, Papillary/blood
- Carcinoma, Papillary/surgery
- Carcinoma, Papillary/therapy
- Female
- Humans
- Iodine Radioisotopes/therapeutic use
- Logistic Models
- Lymphatic Metastasis/diagnosis
- Male
- Middle Aged
- Neoplasm Metastasis/diagnosis
- Prognosis
- Thyroglobulin/blood
- Thyroid Neoplasms/blood
- Thyroid Neoplasms/surgery
- Thyroid Neoplasms/therapy
- Thyroidectomy
- Thyrotropin/blood
- Thyroxine/therapeutic use
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Affiliation(s)
- N Lima
- Endocrine Division, University of Sao Paulo Medical School, SP, Brazil
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29
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Rochitte CE, Kaneko R, Knobel M, Avezum A, Souza JAM, Brito FS, Knobel E. Door-to-balloon time in patients undergoing primary angioplasty and therapeutic decision on acute myocardial infarction. Crit Care 2001. [PMCID: PMC3226131 DOI: 10.1186/cc1334] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Cezar JC, Knobel M, Tolentino HC. Structural properties of Cu-Permalloy under annealing. J Synchrotron Radiat 2001; 8:877-879. [PMID: 11512964 DOI: 10.1107/s0909049501000292] [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] [Received: 07/31/2000] [Accepted: 01/03/2001] [Indexed: 05/23/2023]
Abstract
We have studied the structure of melt-spun copper-permalloy samples (Cu80Fe4Ni16), annealed at several temperatures up to 873 K by means of EXAFS spectroscopy. The results for iron first neighhor average distance showed a slow decrease for annealing temperatures higher than 673 K. The nickel first neighbor distance had almost no change in the whole temperature range. This behavior is discussed in the light of rich iron cluster formation, and is compared with magnetic measurement results.
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Affiliation(s)
- J C Cezar
- LNLS CP6192 CEP 13084-971 Campinas/SP, Brasil.
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Lima N, Cavaliere H, Knobel M, Halpern A, Medeiros-Neto G. Decreased androgen levels in massively obese men may be associated with impaired function of the gonadostat. Int J Obes (Lond) 2000; 24:1433-7. [PMID: 11126339 DOI: 10.1038/sj.ijo.0801406] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE In obese men, sex hormone-binding globulin (SHBG) as well as total testosterone (TT) levels are decreased. Data concerning serum free testosterone (FT) levels in obese men are discordant. FT levels are decreased in only some morbidly obese men, consistent with an impairment of the feedback regulatory mechanism. In this study we aimed to verify serum levels of TT and FT in two groups of obese men (BMI < 35.0 kg/m2 and BMI > 35.1 kg/m2) before and after weight loss. DESIGN Two groups of obese men (group 1: BMI < or = 35 kg/m2; and group 2: BMI > or =35.1 kg/m2) were studied before and after 6 months of a low energy diet (1200 kcal/day). Every patient received a therapeutic prescription of dexfenfluramine (15 mg b.i.d.) that was maintained for 6 months. SUBJECTS Thirty-seven obese men and 20 normal weight men. MEASUREMENTS Serum sex hormones (TT and FT), serum luteinizing hormone (LH) and insulin were analyzed by RIA assays. Plasma insulin levels, serum TT, FT and LH concentrations were obtained before and after weight loss. RESULTS Moderately obese men (BMI = 32.3+/- 1.9 kg/m2) presented significantly decreased TT levels (390+/-120ng/dl) as well as FT (mean+/-s.d.:16.0+/-4.8pg/ml) as compared with normal controls. FT serum levels had a significant and negative correlation with body mass index (BMI), whereas for TT concentrations this correlation was not significant. Serum LH concentrations (4.5+/-2.9mlU/ml) were normal. Insulin levels were elevated in all patients (46.3+/-30.1 microU/ml). After weight loss there was a significant (P< 0.01) increase in TT, FT and LH levels, whereas insulin concentrations significantly decreased. In massively obese men (BMI = 43.0 6.7 kg/m2), TT (320+/-110ng/dl), FT (11.0+/-2.1 pg/ml) and LH (3.1+/-1.3mlU/ml) were decreased and significantly lower as compared with the previous group and normal controls. As expected, after weight loss TT, FT and LH levels increased significantly while insulin concentrations decreased. CONCLUSIONS We concluded that FT levels are dependent on the degree of obesity, massively obese men (BMI > or =35.1 kg/m2) being considered as candidates for consistently low FT levels. A functional decrease of LH pulse amplitude and serum LH levels as well as a possible negative action of excess of circulating leptin on the steroidogenesis may be related to the decreased androgens levels in massively obese men.
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Affiliation(s)
- N Lima
- Endocrine Division, University of São Paulo Medical School, Brazil
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36
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Avezum A, Cavalcanti AB, Sousa AG, Farsky PS, Knobel M. [Adjuvant therapy in acute myocardial infarction: evidence based recommendations]. Rev Assoc Med Bras (1992) 2000; 46:363-8. [PMID: 11175574 DOI: 10.1590/s0104-42302000000400038] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Affiliation(s)
- A Avezum
- Departamento do Cardiologia do Instituto Dante Pazzonese/Hospital Albert Einstein, São Paulo, SP
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Abstract
OBJECTIVE Postpartum thyroid dysfunction (PPTD) is an autoimmune disorder characterized by the development of transient hyperthyroidism and, more frequently, hypothyroidism (or both) during the first six months of the puerperal period. A variable incidence has been reported in part because of differences in the number of women studied, the frequency of thyroid assessment postpartum, diagnostic criteria and methodology. The aim of this study was to evaluate thyroid function, ultrasound images and titre of autoantibodies against thyroid antigens in a cohort of pregnant women who met the criteria of 'normal' thyroid gland structure on clinical examination and imaging and normal thyroid function tests without a significantly positive anti-thyroid peroxidase (TPO) antibody titre (i.e. < 100 U/ml) in the first trimester. DESIGN AND PATIENTS Eight hundred nulliparous or multiparous (one to seven previous pregnancies) pregnant women (age 26.1 +/- 4.8 years, mean +/- SD), were submitted to clinical, laboratory and ultrasonographic examination in the first trimester of pregnancy. Among these forty-six patients were excluded because of thyroid dysfunction, ultrasound structural abnormalities or a positive anti-TPO antibody titre (> 100 U/ml). A total number of 754 women were available for further studies in the postpartum period. A relatively large number of these patients (386) were lost for follow-up either before or after delivery. MEASUREMENTS A cohort of 368 puerperal women was followed up regularly at 3, 6, 12 and 24 months after delivery, with periodic thyroid function tests, random urine iodine measurements, assays for serum autoantibodies against thyroid antigens and imaging by ultrasound. RESULTS The provisional diagnosis of PPTD was established in 78 out of 368 who had positive anti-TPO levels and ultrasonographic thyroid structural changes. Twenty-nine of these patients had a transient rise of anti-TPO autoantibodies characterizing an autoimmune reaction. These autoantibodies levels progressively declined or became negative. Moreover none of these patients had evidence for altered thyroid function during the 18-24 months of follow-up. The remaining 49 patients (13.3%) progressively developed thyroid function abnormalities (mainly hypothyroidism) indicating the presence of thyroid gland changes due to PPTD. Further follow-up studies indicated that at 18-24 months, 42 patients had serum levels of anti-TPO-Ab that were more elevated, as compared with the first year values. Predictive factors found during pregnancy for developing PPTD were: (1) relatively low levels of anti-TPO, between 60 and 100 U/ml (odds ratio 3.1 : 1), and (2) ultrasonographic thyroid structural changes in the first trimester (odds ratio 6.4 : 1). CONCLUSIONS We conclude that the prevalence of postpartum thyroid dysfunction in our geographical area ranges from 6.7% to 13.3%, considering, respectively, all pregnant women that were examined (n = 754) or only the number of puerperal women actually followed-up (n = 368). A transient form of thyroid autoimmune reaction characterized by elevated serum levels of anti-TPO that progressively declined or disappeared was observed in 29 puerperal women. Sonographic structural and echogenicity changes in the thyroid gland and borderline positive anti-TPO levels (between 60 and 100 U/ml) during pregnancy were considered to be of predictive value for development of postpartum thyroid dysfunction.
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Affiliation(s)
- M F Barca
- Thyroid Unit, Division of Endocrinology, Department of Medicine, University of São Paulo Medical School, Brazil
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dos Santos DR, Torriani IL, Silva FCS, Knobel M. In-situsmall-angle scattering study on the formation of a nanocrystalline soft-magnetic alloy. J Appl Crystallogr 2000. [DOI: 10.1107/s0021889899015599] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Abstract
Anti-Gal is a human polyclonal antibody that constitutes approximately 1% of the circulating immunoglobulin G (IgG), interacts specifically with the mammalian carbohydrate alpha-galactosyl epitope. Furthermore, it was found to mimic in vitro thyrotropin (TSH) effects regarding stimulation for cyclic adenosine monophosphate (cAMP) synthesis, 125I uptake, and cellular proliferation on cultured porcine thyrocytes and on Graves' disease thyrocytes, but not on normal human thyrocytes. As immune activation in sporadic and endemic goiters might play a secondary role in regulating thyrocyte proliferation and function, we evaluated anti-Gal titers in endemic goiter. Serum was obtained from 109 Chagas'-negative patients living in an endemic goiter area of Brazil (Grao Mogol, MG) and 160 controls. The patients were divided into 3 groups, according to their goiter size (World Health Organization [WHO] classification): grade 0 (group 1, n = 24), grade I-II (group 2, n = 41), and grade III-IV (group 3, n = 44). Anti-Gal was assessed by a radioimmunological procedure (results expressed as the percentage of bound radioactivity/total activity [%B/T]). The antibody titer was significantly more elevated in group 1 (mean +/- SEM: 9.27%+/-0.80%), in group 2 (mean +/- SEM: 16.17%+/-0.97%), and in group 3 (20.97%+/-1.30%) than in normal controls (6.46%+/-0.33%). Analysis of the male and female data separately for anti-Gal titer did not substantially alter these results. We concluded that the anti-Gal titer is higher in patients with endemic goiter and presented a possible relationship with the size of goiter. Whether these antibodies contribute to the pathogenesis of the disease needs further clarification.
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Affiliation(s)
- M Knobel
- Department of Medicine, University of São Paulo Medical School, Brazil
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40
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Medeiros-Neto G, Bunduki V, Tomimori E, Gomes S, Knobel M, Martin RT, Zugaib M. Prenatal diagnosis and treatment of dyshormonogenetic fetal goiter due to defective thyroglobulin synthesis. J Clin Endocrinol Metab 1997; 82:4239-42. [PMID: 9398747 DOI: 10.1210/jcem.82.12.4407] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- G Medeiros-Neto
- Thyroid Unit, University of São Paulo Medical School, Brazil
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Pohlenz J, Medeiros-Neto G, Gross JL, Silveiro SP, Knobel M, Refetoff S. Hypothyroidism in a Brazilian kindred due to iodide trapping defect caused by a homozygous mutation in the sodium/iodide symporter gene. Biochem Biophys Res Commun 1997; 240:488-91. [PMID: 9388506 DOI: 10.1006/bbrc.1997.7594] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A 36 year old man with a large goiter was suspected of having iodide (I-) transport defect based on low thyroidal and salivary gland radioiodide uptake. Thyroid surgery was performed, because thyroid cytology could not exclude a malignancy. Sequencing of the entire Na+/I- symporter (NIS) cDNA derived from thyroidal mRNA revealed a homozygous substitution of the normal cytosine in nucleotide (nt) 1163 with an adenine, resulting in a stop (TGA) at codon 272. This nonsense mutation produces a truncated NIS with undetectable I- transport activity when expressed into COS-7 cells. Genotyping confirmed that the propositus was homozygous for the mutation whereas his unaffected mother, son, and paternal aunt were heterozygous. This nt substitution was not detected in any of 50 normal individuals, ruling out a polymorphism. While the homozygous mutant NIS-272X causes congenital hypothyroidism, expression of one normal allele in the heterozygote (C272X) is sufficient to maintain active thyroidal I- uptake and function.
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Affiliation(s)
- J Pohlenz
- Department of Medicine, University of Chicago, Illinois 60637-1470, USA
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42
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dos Santos DR, Torriani IL, Ramos AY, Knobel M. Small-Angle X-ray Scattering Study of Nanocrystalline and Amorphous States of the Fe73.5CuNb3Si13.5B9 Alloy. J Appl Crystallogr 1997. [DOI: 10.1107/s0021889897001891] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The structural evolution of the nanocrystalline material obtained from the amorphous compound Fe73.5CuNb3Si13.5B9 was investigated by small-angle X-ray scattering. Four sets of amorphous metallic ribbons were produced by melt spinning using different quenching rates. Samples of each set were annealed above the crystallization temperature; X-ray diffraction analysis showed the formation of an ordered Fe–Si solid solution with average grain sizes ranging from 9 to 11 nm. Small-angle scattering curves of the samples in the initial amorphous states revealed different intensities for different quenching rates, caused by the presence of heterogeneities with dimensions larger than those of the crystallites formed after thermal treatment. In addition, scattering measurements carried out in situ during isothermal annealing showed an intensity evolution as a function of time, attributed to electron-density contrast variation caused by the atomic diffusion process that occurs during crystallization.
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Lima N, Knobel M, Cavaliere H, Sztejnsznajd C, Tomimori E, Medeiros-Neto G. Levothyroxine suppressive therapy is partially effective in treating patients with benign, solid thyroid nodules and multinodular goiters. Thyroid 1997; 7:691-7. [PMID: 9349571 DOI: 10.1089/thy.1997.7.691] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We prospectively evaluated the effect of thyrotropin (TSH)-suppressive therapy with levothyroxine (LT4) on the size of a benign, solitary, solid nodule and multinodular goiter in a relatively low iodine intake area. In this study, 101 euthyroid subjects with a benign, solitary, predominantly solid nodule (n = 54) confirmed by biopsy or multinodular goiter (n = 47) received 200 microg of levothyroxine daily as a single morning tablet for 12 months. Thirty-five receiving no therapy were considered as controls (solitary nodules, n = 20, multinodular, n = 15). Patients were admitted to the study after evaluation of thyroid biochemical parameters (thyroxine [T4], free thyroxine [FT4], triiodothyronine [T3], thyrotropin [TSH], and thyroglobulin [Tg]), thyroid scanning, ultrasound examination, and fine-needle aspiration biopsy. Every 3 months, thyroid function tests and every 6 months ultrasound examinations were repeated. Twelve months later 20 of 54 (37.1%) patients with single, solid nodules had 50% or more regression of the nodular volume (responders). Eleven of 54 (20.3%) patients had more than 20%, but less than 49.9% reduction of nodular volume (partial responders). Nonresponders were 23 of 54 (42.5%). One-third of subjects with multinodular goiter had 50% or more regression of the glandular volume, whereas 46.8% were considered as nonresponsive. The mean serum Tg levels decreased significantly only in responders with solitary nodular disease or multinodular goiter. In the control group only 1 patient (5% of total) with a solitary nodule had a 50% reduction in the nodular volume. Five others had a partial response (<49%, >20% reduction). None of the patients with multinodular goiter had a significant reduction (>50%) of the combined nodular volumes. We concluded that LT4 may be effective, among other factors, in arresting the growth or in reducing the volume of relatively small, benign, solitary, solid thyroid nodules or the combined nodular volume of multinodular goiter.
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Affiliation(s)
- N Lima
- Department of Medicine, University of Sao Paulo Medical School, Brazil
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Vono J, Lima N, Knobel M, Medeiros-Neto G. The effect of oral administration of iodine to patients with goiter and hypothyroidism due to defective synthesis of thyroglobulin. Thyroid 1996; 6:11-5. [PMID: 8777378 DOI: 10.1089/thy.1996.6.11] [Citation(s) in RCA: 6] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The effects of administration of iodine (1 mg/day orally, 64 days) were studied in three siblings with congenital goiter and hypothyroidism due to defective thyroglobulin (Tg) synthesis. The patients presented very large goiters, elevated RAI uptake, negative perchlorate discharge test, low serum T4, and elevated TSH concentrations. Immunoassayable Tg was low and failed to increase after stimulation with exogenous bovine TSH. Analysis of individual thyroid extracts by gel filtration failed to reveal a Tg component; the immunoassayable Tg antigens in these goitrous tissues were 0.12 and 0.21 mg/g tissue, respectively (normal 70-90 mg/g tissue). The histological pattern of their thyroids was compatible with defective Tg synthesis. The administration of iodine caused a rise in the mean serum T4, T3, and free T4 concentrations in all three siblings, but did not alter the serum Tg concentration. TSH concentrations rose in the terminal period of observation in the three subjects and this was considered to be due to a possible effect produced by the iodine load in the thyroperoxidase system (Wolff-Chaikoff effect). One patient showed an increase in goiter size during the period of observation. These results suggest that iodine administration enhanced the ability of the dyshormonogenetic gland to synthesize iodothyronines.
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Affiliation(s)
- J Vono
- Thyroid Unit, University of São Paulo Medical School, Brazil
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45
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Allia P, Knobel M, Tiberto P, Vinai F. Magnetic properties and giant magnetoresistance of melt-spun granular Cu100-x-Cox alloys. Phys Rev B Condens Matter 1995; 52:15398-15411. [PMID: 9980898 DOI: 10.1103/physrevb.52.15398] [Citation(s) in RCA: 196] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Abstract
An ultrasonographic survey of thyroid abnormalities was conducted in 547 consecutive apparently normal overweight subjects (380 females and 167 males), aged 27-58 years in an urban area with relatively low iodine intake (mean daily urinary iodine excretion: 10.6 micrograms/dL). Individuals with any previous thyroid disease or familial thyroid pathology were excluded. In 240 subjects (44%) high resolution ultrasonography of the thyroid was considered normal. In 307 individuals (56%) abnormalities of the echo structure (39%) or thyroid nodular disease (17%) were detected by ultrasonography. Marked heterogeneity of the echo structure that was considered suggestive of chronic autoimmune thyroiditis was present in 81 subjects (15%). In 72 of these patients the serum anti-TPO levels were positive by a sensitive RIA. Thyroid nodules either solid or predominantly cystic were present in 90 subjects (17%). Eighteen patients had a relatively large nodule (diameter 15-18 mm). Eleven of these nodules were missed at clinical examination. Fine needle aspiration cytology was performed in 14 patients and 7 individuals underwent thyroid surgery. In 6 subjects the pathologic diagnosis was benign adenomatous goiter and one patient had a follicular carcinoma. Thyroid function studies confirmed subclinical hypothyroidism in 27 patients (4.9%), all of them with elevated serum anti-TPO autoantibodies levels. It was concluded that the overall occurrence of thyroid disease is more common than suspected by clinical examination.
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Affiliation(s)
- E Tomimori
- Thyroid Unit, University of São Paulo Medical School, Brazil
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47
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Knobel M, Barca MF, Pedrinola F, Medeiros-Neto G. Prevalence of anti-thyroid peroxidase antibodies in autoimmune and nonautoimmune thyroid disorders in a relatively low-iodine environment. J Endocrinol Invest 1994; 17:837-42. [PMID: 7745231 DOI: 10.1007/bf03347788] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We evaluated the prevalence of antithyroid peroxidase antibodies (anti-TP0 Ab) in 402 patients with thyroid disease and 30 healthy controls by a commercial radioimmunoassay (RIA) and compared the results with the passive hemagglutination (HA) method. The patients in the study had autoimmune thyroid disorders (AITD) such as Graves' disease and Hashimoto's disease or had nonautoimmune thyroid diseases (NAITD) such as thyroid cancer, congenital goiter, endemic goiter, and nodular goiter. Subjects were recruited from a population with a mild iodine deficiency (Sao Paulo, Brazil). The effect of specific therapy (for either thyrotoxicosis or chronic thyroiditis) on the circulating anti-TPO levels was also investigated. Positive anti-TPO Ab was detected in 89.9% of the patients with AITD as compared with a prevalence of positive tests of only 4.8% in patients with NAITD. Positive microsomal antibody (M Ab) was found in 68.4% of the patients with AITD and in 6.4% of the patients with NAITD. A positive and significant correlation was obtained between M Ab and anti-TPO Ab. A positive anti-TPO test with negative anti-M was found in 14.1% of the patients with AITD but in only 4.3% of the patients with NAITD and normal controls. These results suggest that anti-TPO Ab by RIA is more sensitive and specific than M Ab by HA. In patients with AITD, anti-TPO Ab levels usually decreased after treatment, suggesting that this parameter could be used in the follow-up of these thyroid disorders.
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Affiliation(s)
- M Knobel
- Thyroid Laboratory, Hospital das Clínicas, University of Sao Paulo Medical School, Brazil
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48
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Perozim LM, Lima N, Knobel M, Cavaliere H, Medeiros-Neto G. Treatment of Graves' disease: effects of the administration of L-thyroxine associated with methimazole as a single daily dose. Eur J Med 1993; 2:70-4. [PMID: 8258020] [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] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
OBJECTIVES To reduce the number of tablets to be administered daily during antithyroid drug (ATD) treatment of Graves' disease (GD) and to evaluate the effectiveness of adding thyroxine after the patients had become euthyroid during methimazole therapy. PATIENTS AND METHODS All patients were given gelatin capsules with 30 mg of methimazole 2 times per day for 4-6 weeks, followed by two capsules with 20 mg of methimazole and 75 micrograms of thyroxine to be taken once a day for 18-24 months. Thirty patients with Graves' disease without previous treatment for hyperthyroidism were included. Two were lost to follow-up and 28 (24 women and 4 men; age range 14-53 years; mean 34.2 years) were followed for 18 to 24 months with methimazole and thyroxine medication plus an additional 2 years after the treatment was suspended. After completion of the study the patients were, retrospectively, divided in two groups: group 1 (G1, n = 20) patients considered to be in remission, and group 2 (G2, n = 8) with persistent active Graves' disease. RESULTS All patients in group 1 had a significant reduction in the glandular mass, as estimated by ultrasonographic studies (mean +/- SD 67 +/- 13 g to 18 +/- 3 g, p < 0.01) whereas subjects in group 2 had no significant reduction in glandular mass (67 +/- 14 g to 53 +/- 16 g). Thyroglobulin levels (mean +/- SD) in G1 were 54 +/- 55 micrograms/L at baseline and decreased to 15 +/- 9 micrograms/L (p < 0.001), and in G2 thyroglobulin concentrations did not decrease significantly after therapy (58 +/- 20 micrograms/L vs 44 +/- 22 micrograms/L). Also, levels of thyroid-stimulating hormone receptor inhibiting antibody (TRAb) only decreased in G1 (49-21% to 8 +/- 5%; p < 0.001). Nineteen patients (all from G1), were euthyroid 2 years after treatment withdrawal, indicating a remission rate of 67.8%. CONCLUSION The administration of L-thyroxine during anti-thyroid drug treatment, with subsequent inhibition of thyroid-stimulating hormone secretion, may be an important factor in glandular mass reduction, decreasing both the production of antibodies to thyroid-stimulating hormone receptors and the frequency of recurrence of hyperthyroidism.
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Affiliation(s)
- L M Perozim
- Thyroid Laboratory, Hospital das Clínicas, University of Sao Paulo Medical School, Brazil
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Knobel M. [Brief psychotherapy in clinical medicine patients]. Actas Luso Esp Neurol Psiquiatr Cienc Afines 1992; 20:263-6. [PMID: 1288068] [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] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The criteria that "illness is biographical crisis od the individual" and that the only medicine is "personal medicine" is stressed. Clinical medicine, which covers medicine in its entirety, demands conceptual and doctrinal reaffirmations so that gradually the patient can come to be dealt with as a human being fron a holistic point of view, which commences with his complaint and consultation, continues with the interview and semiology, to finish with the diagnosis and therapy which, although in some cases it may be surgical, is still medical and integral. All the steps mentioned are bio-socio-cultural thus, whether in the practice of general clinical medicine or in the most specialized and technologically sophisticated clinical medicine, the animist component is not lacking and demands a minimum degree of "psychosomatic" Knowledge. The use of a psychotherapeutic technique is proposed which, while based on the psychoanalysis theory, is distanced technically from it as a "psychotherapy on limited time and goals", which abbreviates the disease, and is projected not as the "focus" of therapeutic work, but as a re-evaluation of the "life style" of each individual, and tends to help to develop a "project for life" suited to the possible personal, familiar and social well-being of the "patient". Technically speaking, this modality of brief psychotherapy is based on the nonuse of transferential interpretations, on impeding the regression od the patient, on facilitating a cognitice-affective development of his conflicts and thus obtain an internal object mutation which allows the transformation of the "past" into true history, and the "present" into vital perspectives. This technique is within reach of every health professional.
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Affiliation(s)
- M Knobel
- Clínica Psiquiátrica, F. C. M. Unicamp, Campinas, SP, Brasil
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Iacona A, Lima N, Perozim LM, Knobel M, Cavaliere H, Medeiros-Neto G. The challenge of treating Graves'-Basedow's disease patients with antithyroid drugs (ATD) in a large university hospital. Exp Clin Endocrinol 1991; 97:297-302. [PMID: 1717299 DOI: 10.1055/s-0029-1211081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- A Iacona
- Thyroid Laboratory, Hospital das Clinicas, Sao Paulo, Brazil
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