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Menezes Fernandes R, Brandão M, Ladeiras Lopes R, Faria R, Dias Ferreira N, Fontes-Carvalho R. Myocardial deformation analysis using cardiac magnetic resonance in apical hypertrophic cardiomyopathy: is it an useful tool to predict adverse outcomes? Int J Cardiovasc Imaging 2023; 39:1997-2003. [PMID: 37421577 DOI: 10.1007/s10554-023-02902-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Accepted: 06/16/2023] [Indexed: 07/10/2023]
Abstract
Apical hypertrophic cardiomyopathy (AHCM) has a broad phenotypic spectrum and still poses many diagnostic and prognostic challenges. Our team performed a retrospective study to examine the prognostic value of myocardial deformation obtained with cardiac magnetic resonance tissue tracking (CMR-TT) analysis in predicting adverse events in AHCM patients. We included patients with AHCM referred to CMR in our department from August 2009 to October 2021. CMR-TT analysis was performed to characterize the myocardial deformation pattern. Clinical, other complementary diagnostic exams characteristics and follow-up data were analysed. Primary endpoint was the composite of all-cause hospitalizations and mortality. During the 12-year period, 51 AHCM patients were evaluated by CMR, with a median age of 64 years-old and male predominance. 56,9% had an echocardiogram suggestive of AHCM. The most frequent phenotype was "the relative form" (43,1%). CMR evaluation revealed a median maximum left ventricle thickness of 15 mm and the presence of late gadolinium enhancement in 78,4%. Applying CMR-TT analysis, median global longitudinal strain was - 14,4%, with a median global radial strain of 30,4% and global circumferential strain of -18,0%. During a median follow-up of 5,3 years, the primary endpoint occurred in 21,3% of patients, with a hospitalization rate of 17,8% and all-cause mortality rate of 6,4%. After multivariable analysis, longitudinal strain rate in apical segments was an independent predictor of the primary endpoint (p = 0,023), showing that CMR-TT analysis could be useful in predicting adverse events in AHCM patients.
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Affiliation(s)
- Raquel Menezes Fernandes
- Cardiology Department, Centro Hospitalar Universitário do Algarve - Hospital de Faro, Faro, Portugal.
- Algarve Biomedical Center, Faro, Portugal.
| | - Mariana Brandão
- Cardiology Department, Centro Hospitalar de Vila Nova de Gaia/Espinho, Vila Nova de Gaia, Portugal
| | - Ricardo Ladeiras Lopes
- Cardiology Department, Centro Hospitalar de Vila Nova de Gaia/Espinho, Vila Nova de Gaia, Portugal
- Cardiovascular R&D Centre - UnIC@RISE, Department of Surgery and Physiology, Faculdade de Medicina da Universidade do Porto, Porto, Portugal
| | - Rita Faria
- Cardiology Department, Centro Hospitalar de Vila Nova de Gaia/Espinho, Vila Nova de Gaia, Portugal
| | - Nuno Dias Ferreira
- Cardiology Department, Centro Hospitalar de Vila Nova de Gaia/Espinho, Vila Nova de Gaia, Portugal
| | - Ricardo Fontes-Carvalho
- Cardiology Department, Centro Hospitalar de Vila Nova de Gaia/Espinho, Vila Nova de Gaia, Portugal
- Cardiovascular R&D Centre - UnIC@RISE, Department of Surgery and Physiology, Faculdade de Medicina da Universidade do Porto, Porto, Portugal
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Menezes Fernandes R, Faria da Mota T. A rare ventriculography: midventricular Takotsubo syndrome. Am J Med Sci 2023; 365:e59-e60. [PMID: 36283424 DOI: 10.1016/j.amjms.2022.10.009] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 09/14/2022] [Accepted: 10/17/2022] [Indexed: 12/25/2022]
Affiliation(s)
- Raquel Menezes Fernandes
- Cardiology Department, Centro Hospitalar Universitário do Algarve, Faro, Portugal; Algarve Biomedical Center, Universidade do Algarve, Faro, Portugal.
| | - Teresa Faria da Mota
- Cardiology Department, Centro Hospitalar Universitário do Algarve, Faro, Portugal; Algarve Biomedical Center, Universidade do Algarve, Faro, Portugal
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Oliveira AKM, Matias R, Lacerda-Pereira KC, Rizzi ES, Fernandes RM. The monodominance of Acuri in Pantanal formations: allelochemical effects of its leaves and the presence of Acurizais. BRAZ J BIOL 2023; 83:e268746. [PMID: 36790277 DOI: 10.1590/1519-6984.268746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 01/24/2023] [Indexed: 02/16/2023] Open
Abstract
The presence of monodominant vegetative formations almost exclusively composed of Acuri palm trees (Attalea phalerata) stands out in some regions of the Pantanal Sul-Mato-Grossense. These formations are generally associated with anthropic, edaphic and/or hydrological factors. However, little is known about the effect of allelopathy on the formation and maintenance of these areas. Herein, we investigated the chemical composition of A. phalerata aqueous leaf extract and the potential allelopathic effects on germination and growth of target L. sativa, L. esculentum and S. obtusifolia species. Thus, extracts at concentrations of 0, 2.5, 5, 10, 15, and 20% were used for germination and growth bioassays with a completely randomised design in a germination chamber and greenhouse. The results showed that the A. phalerata extracts negatively affected the germination speed index and mean germination time of the target species and positively affected seedling length under controlled conditions and were also stimulated in the greenhouse. Thus, the formation of Acurizals can be related to the presence of secondary metabolites in the leaves, in addition to other environmental factors.
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Affiliation(s)
- A K M Oliveira
- Universidade Anhanguera - Uniderp, Campo Grande, MS, Brasil
| | - R Matias
- Universidade Anhanguera - Uniderp, Campo Grande, MS, Brasil
| | | | - E S Rizzi
- Universidade Anhanguera - Uniderp, Campo Grande, MS, Brasil
| | - R M Fernandes
- Universidade Anhanguera - Uniderp, Campo Grande, MS, Brasil
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Fernandes RM, Bento D, Marques N, Azevedo O, Mota T, Costa H, Santo ME, Silva DC, Jesus I. Challenges in Fabry disease: the combination of two individually amenable GLA variants may be nonamenable to migalastat. Future Cardiol 2023; 19:39-43. [PMID: 36695159 DOI: 10.2217/fca-2022-0080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Fabry disease is a rare lysosomal storage disorder caused by mutations in the GLA gene, resulting in reduced or absent α-Gal A activity. Migalastat is an oral chaperone therapy for Fabry patients with amenable GLA variants. We previously reported a case of a 60-year-old male patient with a classic phenotype of Fabry disease, presenting with two GLA variants: p.R356Q and p.G360R. Herein, we report that, although these two missense variants are individually classified as amenable to migalastat in the validated in vitro human embryonic kidney-293 cell-based assay, their combination precludes the patient to be treated with this oral chaperone. This case illustrates how therapeutic decisions may be challenging and how a good genotypic characterization of Fabry patients is critical for the selection of the correct therapeutic strategy.
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Affiliation(s)
- Raquel Menezes Fernandes
- Department of Cardiology, Centro Hospitalar Universitário do Algarve-Hospital de Faro, Faro, 8000-386, Portugal.,Algarve Biomedical Center, Faro, 8005-139, Portugal
| | - Dina Bento
- Department of Cardiology, Centro Hospitalar Universitário do Algarve-Hospital de Faro, Faro, 8000-386, Portugal.,Algarve Biomedical Center, Faro, 8005-139, Portugal
| | - Nuno Marques
- Algarve Biomedical Center, Faro, 8005-139, Portugal.,Faculdade de Medicina e Ciências Biomédicas, University of Algarve, Faro, 8005-139, Portugal
| | - Olga Azevedo
- Department of Cardiology, Reference Center of Lysosomal Storage Disorders, Hospital Senhora da Oliveira-Guimarães, Guimarães, 4835-044, Portugal.,Life & Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, 4710-057, Portugal.,ICVS/3Bs PT Government Associate Laboratory, Guimarães, 4806-909, Portugal
| | - Teresa Mota
- Department of Cardiology, Centro Hospitalar Universitário do Algarve-Hospital de Faro, Faro, 8000-386, Portugal.,Algarve Biomedical Center, Faro, 8005-139, Portugal
| | - Hugo Costa
- Department of Cardiology, Centro Hospitalar Universitário do Algarve-Hospital de Faro, Faro, 8000-386, Portugal.,Algarve Biomedical Center, Faro, 8005-139, Portugal
| | - Miguel Espírito Santo
- Department of Cardiology, Centro Hospitalar Universitário do Algarve-Hospital de Faro, Faro, 8000-386, Portugal.,Algarve Biomedical Center, Faro, 8005-139, Portugal
| | - Daniela Carvalho Silva
- Department of Cardiology, Centro Hospitalar Universitário do Algarve-Hospital de Faro, Faro, 8000-386, Portugal.,Algarve Biomedical Center, Faro, 8005-139, Portugal
| | - Ilídio Jesus
- Department of Cardiology, Centro Hospitalar Universitário do Algarve-Hospital de Faro, Faro, 8000-386, Portugal.,Algarve Biomedical Center, Faro, 8005-139, Portugal
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Menezes Fernandes R, Mota T, Costa H, Bispo J, Azevedo P, Bento D, Guedes J, Carvalho D, Marques N, Santos W, Mimoso J, de Jesus I. Premature acute coronary syndrome: understanding the early onset. Coron Artery Dis 2022; 33:456-464. [PMID: 35190516 DOI: 10.1097/mca.0000000000001141] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [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
INTRODUCTION Acute coronary syndrome (ACS) is less frequent in young adults, but it has become a significant health problem, associated with the increasing prevalence of modifiable risk factors. OBJECTIVES To characterize patients admitted with premature ACS, comparing with those with nonpremature ACS. METHODS We performed a retrospective study encompassing patients of the Portuguese Registry (ProACS), comparing two groups: one composed of men less than 55 and women less than 65 years old; and other with men ≥55 and women ≥65 years old at the ACS admission. The primary endpoint was the composite of in-hospital mortality, stroke and myocardial reinfarction (re-MI). RESULTS A total of 29 870 patients were enrolled and 25% had premature ACS, with a mean age of 50 ± 7 years old. They had a larger prevalence of smoking habits, obesity and dyslipidemia. ST-segment elevation MI (STEMI) was the main admission diagnosis in young patients and coronary angiogram mainly revealed one vessel disease in this subgroup. They had a lower Killip-Kimball (KK) class and mostly preserved left ventricular ejection fraction (LVEF). Composite endpoint was more frequent in nonpremature ACS patients. Nonpremature age, presentation with syncope or cardiac arrest, KK class >1, multivessel disease and LVEF <40% were independent predictors of the primary endpoint ( P < 0.001). Younger patients had lower rates of in-hospital all-cause mortality, re-MI and stroke. One-year all-cause mortality and 1-year cardiovascular and non-cardiovascular readmissions were also lower. CONCLUSIONS Premature ACS affects 25% of the ACS population, mostly presenting with STEMI, but generally associated with better clinical evolution. Nevertheless, prevention measures are essential to correct modifiable cardiovascular risk factors and reduce coronary events.
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Affiliation(s)
| | - Teresa Mota
- Cardiology Deparment, Centro Hospitalar Universitário do Algarve
- Algarve Biomedical Center, Faro
| | - Hugo Costa
- Cardiology Deparment, Centro Hospitalar Universitário do Algarve
- Algarve Biomedical Center, Faro
| | - João Bispo
- Cardiology Deparment, Centro Hospitalar Universitário do Algarve
- Algarve Biomedical Center, Faro
| | - Pedro Azevedo
- Cardiology Deparment, Centro Hospitalar Universitário do Algarve
- Algarve Biomedical Center, Faro
| | - Dina Bento
- Cardiology Deparment, Centro Hospitalar Universitário do Algarve
- Algarve Biomedical Center, Faro
- Medical and Biomedical Department, University of Algarve, Portugal
| | - João Guedes
- Cardiology Deparment, Centro Hospitalar Universitário do Algarve
- Algarve Biomedical Center, Faro
| | - Daniela Carvalho
- Cardiology Deparment, Centro Hospitalar Universitário do Algarve
- Algarve Biomedical Center, Faro
| | - Nuno Marques
- Cardiology Deparment, Centro Hospitalar Universitário do Algarve
- Algarve Biomedical Center, Faro
- Medical and Biomedical Department, University of Algarve, Portugal
| | - Walter Santos
- Cardiology Deparment, Centro Hospitalar Universitário do Algarve
- Algarve Biomedical Center, Faro
| | - Jorge Mimoso
- Cardiology Deparment, Centro Hospitalar Universitário do Algarve
- Algarve Biomedical Center, Faro
| | - Ilídio de Jesus
- Cardiology Deparment, Centro Hospitalar Universitário do Algarve
- Algarve Biomedical Center, Faro
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Najev A, Hameed S, Gautreau D, Wang Z, Joe J, Požek M, Birol T, Fernandes RM, Greven M, Pelc D. Uniaxial Strain Control of Bulk Ferromagnetism in Rare-Earth Titanates. Phys Rev Lett 2022; 128:167201. [PMID: 35522519 DOI: 10.1103/physrevlett.128.167201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 10/26/2021] [Accepted: 03/04/2022] [Indexed: 06/14/2023]
Abstract
The perovskite rare-earth titanates are model Mott insulators with magnetic ground states that are very sensitive to structural distortions. These distortions couple strongly to the orbital degrees of freedom and, in principle, it should be possible to tune the superexchange and the magnetic transition with strain. We investigate the representative system (Y,La,Ca)TiO_{3}, which exhibits low crystallographic symmetry and no structural instabilities. From magnetic susceptibility measurements of the Curie temperature, we demonstrate direct, reversible, and continuous control of ferromagnetism by influencing the TiO_{6} octahedral tilts and rotations with uniaxial strain. The relative change in T_{C} as a function of strain is well described by ab initio calculations, which provides detailed understanding of the complex interactions among structural, orbital, and magnetic properties in rare-earth titanates. The demonstrated manipulation of octahedral distortions opens up far-reaching possibilities for investigations of electron-lattice coupling, competing ground states, and magnetic quantum phase transitions in a wide range of quantum materials.
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Affiliation(s)
- A Najev
- Department of Physics, Faculty of Science, University of Zagreb, Bijenička 32, HR-10000 Zagreb, Croatia
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - S Hameed
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - D Gautreau
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - Z Wang
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - J Joe
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - M Požek
- Department of Physics, Faculty of Science, University of Zagreb, Bijenička 32, HR-10000 Zagreb, Croatia
| | - T Birol
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - R M Fernandes
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - M Greven
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - D Pelc
- Department of Physics, Faculty of Science, University of Zagreb, Bijenička 32, HR-10000 Zagreb, Croatia
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
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Hameed S, Pelc D, Anderson ZW, Klein A, Spieker RJ, Yue L, Das B, Ramberger J, Lukas M, Liu Y, Krogstad MJ, Osborn R, Li Y, Leighton C, Fernandes RM, Greven M. Enhanced superconductivity and ferroelectric quantum criticality in plastically deformed strontium titanate. Nat Mater 2022; 21:54-61. [PMID: 34608284 DOI: 10.1038/s41563-021-01102-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Accepted: 08/11/2021] [Indexed: 06/13/2023]
Abstract
The properties of quantum materials are commonly tuned using experimental variables such as pressure, magnetic field and doping. Here we explore a different approach using irreversible, plastic deformation of single crystals. We show that compressive plastic deformation induces low-dimensional superconductivity well above the superconducting transition temperature (Tc) of undeformed SrTiO3, with evidence of possible superconducting correlations at temperatures two orders of magnitude above the bulk Tc. The enhanced superconductivity is correlated with the appearance of self-organized dislocation structures, as revealed by diffuse neutron and X-ray scattering. We also observe deformation-induced signatures of quantum-critical ferroelectric fluctuations and inhomogeneous ferroelectric order using Raman scattering. Our results suggest that strain surrounding the self-organized dislocation structures induces local ferroelectricity and quantum-critical dynamics that strongly influence Tc, consistent with a theory of superconductivity enhanced by soft polar fluctuations. Our results demonstrate the potential of plastic deformation and dislocation engineering for the manipulation of electronic properties of quantum materials.
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Affiliation(s)
- S Hameed
- School of Physics and Astronomy, University of Minnesota, Minneapolis, MN, USA
| | - D Pelc
- School of Physics and Astronomy, University of Minnesota, Minneapolis, MN, USA.
- Department of Physics, Faculty of Science, University of Zagreb, Zagreb, Croatia.
| | - Z W Anderson
- School of Physics and Astronomy, University of Minnesota, Minneapolis, MN, USA
| | - A Klein
- Department of Physics, Faculty of Natural Sciences, Ariel University, Ariel, Israel
| | - R J Spieker
- School of Physics and Astronomy, University of Minnesota, Minneapolis, MN, USA
| | - L Yue
- International Center for Quantum Materials, School of Physics, Peking University, Beijing, China
| | - B Das
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN, USA
| | - J Ramberger
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN, USA
| | - M Lukas
- Faculty of Mechanical Engineering and Naval Architecture, University of Zagreb, Zagreb, Croatia
| | - Y Liu
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - M J Krogstad
- Materials Science Division, Argonne National Laboratory, Lemont, IL, USA
| | - R Osborn
- Materials Science Division, Argonne National Laboratory, Lemont, IL, USA
| | - Y Li
- International Center for Quantum Materials, School of Physics, Peking University, Beijing, China
| | - C Leighton
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN, USA
| | - R M Fernandes
- School of Physics and Astronomy, University of Minnesota, Minneapolis, MN, USA
| | - M Greven
- School of Physics and Astronomy, University of Minnesota, Minneapolis, MN, USA.
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Menezes Fernandes R, Nuñez D, Marques N, Dias CC, Granja C. Surviving cardiac arrest: What happens after admission to the intensive care unit? Rev Port Cardiol 2021; 40:317-325. [PMID: 34187632 DOI: 10.1016/j.repce.2020.07.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 01/18/2020] [Accepted: 07/14/2020] [Indexed: 11/28/2022] Open
Abstract
INTRODUCTION Patients successfully resuscitated from cardiac arrest (CA) are admitted to the intensive care unit (ICU) for post-resuscitation care. These patients' prognosis remains dismal, with only a minority surviving to hospital discharge. Understanding the clinical factors involved in the management of these patients is essential to improve their prognosis. OBJECTIVES To characterize the population admitted after successful reanimation from CA, and to analyze the factors associated with their outcomes. METHODS We performed a retrospective descriptive study of patients admitted to an ICU after CA over a five-year period from January 2014 to December 2018. Demographic factors, CA characteristics, early management, mortality and neurologic outcomes were analyzed. RESULTS A total of 187 patients, median age 67 years, were admitted after CA, of whom 39% suffered out-of-hospital CA; 87% had an initial non-shockable rhythm and the most frequent presumed cause was cardiac (31%). In-hospital mortality was 63%. Significant neurologic dysfunction (cerebral performance category 3 or 4) was seen in 31% of survivors at hospital discharge. Non-immediate initiation of basic life support (BLS), higher Simplified Acute Physiology Score II score and longer relative duration of vasopressor support were independent predictors of in-hospital mortality, while shockable rhythms were associated with improved survival. Higher Glasgow coma scale at ICU discharge and shorter length of ICU stay were predictors of better neurologic outcome. CONCLUSION This study highlights the positive prognostic impact of shockable rhythms, and confirms the importance of immediate initiation of BLS and prompt defibrillation, supporting the need for better training both outside and inside hospitals.
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Affiliation(s)
- Raquel Menezes Fernandes
- Cardiology Department, Centro Hospitalar Universitário do Algarve, Faro, Portugal; Algarve Biomedical Center, Faro, Portugal.
| | - Daniel Nuñez
- Intensive Care Department, Centro Hospitalar Universitário do Algarve, Portugal; Medical and Biomedical Department, University of Algarve, Portugal; Algarve Biomedical Center, Faro, Portugal
| | - Nuno Marques
- Cardiology Department, Centro Hospitalar Universitário do Algarve, Faro, Portugal; Medical and Biomedical Department, University of Algarve, Portugal; Algarve Biomedical Center, Faro, Portugal
| | - Cláudia Camila Dias
- CINTESIS - Center for Health Technology and Services Research, Portugal; MEDCIDS - Department of Community Medicine, Information and Health Decision, Faculty of Medicine of Porto, Portugal
| | - Cristina Granja
- CINTESIS - Center for Health Technology and Services Research, Portugal; Anesthesiology Department, Centro Hospitalar Universitário São João, Porto, Portugal; Surgery and Physiology Department, Faculty of Medicine of Porto, Porto, Portugal
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9
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Menezes Fernandes R, Nuñez D, Marques N, Dias CC, Granja C. Surviving cardiac arrest: What happens after admission to the intensive care unit? Rev Port Cardiol 2021; 40:317-325. [PMID: 33812706 DOI: 10.1016/j.repc.2020.07.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [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: 01/18/2020] [Revised: 06/02/2020] [Accepted: 07/14/2020] [Indexed: 10/21/2022] Open
Abstract
INTRODUCTION Patients successfully resuscitated from cardiac arrest (CA) are admitted to the intensive care unit (ICU) for post-resuscitation care. These patients' prognosis remains dismal, with only a minority surviving to hospital discharge. Understanding the clinical factors involved in the management of these patients is essential to improve their prognosis. OBJECTIVES To characterize the population admitted after successful reanimation from CA, and to analyze the factors associated with their outcomes. METHODS We performed a retrospective descriptive study of patients admitted to an ICU after CA over a five-year period from January 2014 to December 2018. Demographic factors, CA characteristics, early management, mortality and neurologic outcomes were analyzed. RESULTS A total of 187 patients, median age 67 years, were admitted after CA, of whom 39% suffered out-of-hospital CA; 87% had an initial non-shockable rhythm and the most frequent presumed cause was cardiac (31%). In-hospital mortality was 63%. Significant neurologic dysfunction (cerebral performance category 3 or 4) was seen in 31% of survivors at hospital discharge. Non-immediate initiation of basic life support (BLS), higher Simplified Acute Physiology Score II score and longer relative duration of vasopressor support were independent predictors of in-hospital mortality, while shockable rhythms were associated with improved survival. Higher Glasgow coma scale at ICU discharge and shorter length of ICU stay were predictors of better neurologic outcome. CONCLUSION This study highlights the positive prognostic impact of shockable rhythms, and confirms the importance of immediate initiation of BLS and prompt defibrillation, supporting the need for better training both outside and inside hospitals.
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Affiliation(s)
- Raquel Menezes Fernandes
- Cardiology Department, Centro Hospitalar Universitário do Algarve, Faro, Portugal; Algarve Biomedical Center, Faro, Portugal.
| | - Daniel Nuñez
- Intensive Care Department, Centro Hospitalar Universitário do Algarve, Portugal; Medical and Biomedical Department, University of Algarve, Portugal; Algarve Biomedical Center, Faro, Portugal
| | - Nuno Marques
- Cardiology Department, Centro Hospitalar Universitário do Algarve, Faro, Portugal; Medical and Biomedical Department, University of Algarve, Portugal; Algarve Biomedical Center, Faro, Portugal
| | - Cláudia Camila Dias
- CINTESIS - Center for Health Technology and Services Research, Portugal; MEDCIDS - Department of Community Medicine, Information and Health Decision, Faculty of Medicine of Porto, Portugal
| | - Cristina Granja
- CINTESIS - Center for Health Technology and Services Research, Portugal; Anesthesiology Department, Centro Hospitalar Universitário São João, Porto, Portugal; Surgery and Physiology Department, Faculty of Medicine of Porto, Porto, Portugal
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10
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Thomas SM, Santos FB, Christensen MH, Asaba T, Ronning F, Thompson JD, Bauer ED, Fernandes RM, Fabbris G, Rosa PFS. Evidence for a pressure-induced antiferromagnetic quantum critical point in intermediate-valence UTe 2. Sci Adv 2020; 6:eabc8709. [PMID: 33055167 PMCID: PMC7556831 DOI: 10.1126/sciadv.abc8709] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 08/27/2020] [Indexed: 06/01/2023]
Abstract
UTe2 is a recently discovered unconventional superconductor that has attracted much interest because of its potentially spin-triplet topological superconductivity. Our ac calorimetry, electrical resistivity, and x-ray absorption study of UTe2 under applied pressure reveals key insights on the superconducting and magnetic states surrounding pressure-induced quantum criticality at P c1 = 1.3 GPa. First, our specific heat data at low pressures, combined with a phenomenological model, show that pressure alters the balance between two closely competing superconducting orders. Second, near 1.5 GPa, we detect two bulk transitions that trigger changes in the resistivity, which are consistent with antiferromagnetic order, rather than ferromagnetism. Third, the emergence of magnetism is accompanied by an increase in valence toward a U4+ (5f 2) state, which indicates that UTe2 exhibits intermediate valence at ambient pressure. Our results suggest that antiferromagnetic fluctuations may play a more substantial role on the superconducting state of UTe2 than previously thought.
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Affiliation(s)
- S M Thomas
- Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
| | - F B Santos
- Los Alamos National Laboratory, Los Alamos, NM 87545, USA
- Escola de Engenharia de Lorena, Universidade de Sao Paulo (EEL-USP), Materials Engineering Department (Demar), Lorena, Sao Paolo, Brazil
| | - M H Christensen
- School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455, USA
| | - T Asaba
- Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - F Ronning
- Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - J D Thompson
- Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - E D Bauer
- Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - R M Fernandes
- School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455, USA
| | - G Fabbris
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439, USA
| | - P F S Rosa
- Los Alamos National Laboratory, Los Alamos, NM 87545, USA
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11
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Fernandes RM, Mota T, Azevedo P, Cunha S, Bento D, Marques N, Bettencourt N, Pereira S, Nobre Â, de Jesus I. Giant Left Ventricular (Pseudo?) Aneurysm Complicating Anterior Myocardial Infarction. JACC Case Rep 2020; 3:334-338. [PMID: 34317530 PMCID: PMC8310941 DOI: 10.1016/j.jaccas.2020.05.103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 05/05/2020] [Indexed: 11/28/2022]
Abstract
The differential diagnosis of true aneurysms and pseudoaneurysms is challenging, and multimodality cardiac imaging is often necessary. We report a case in which the limitations of these techniques are exposed, showing that post-operative evaluation of tissue layers remains the gold standard in establishing this diagnosis. (Level of Difficulty: Beginner.)
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Affiliation(s)
- Raquel Menezes Fernandes
- Cardiology Department, Centro Hospitalar Universitário do Algarve, Faro, Portugal.,Algarve Biomedical Center, Faro, Portugal
| | - Teresa Mota
- Cardiology Department, Centro Hospitalar Universitário do Algarve, Faro, Portugal.,Algarve Biomedical Center, Faro, Portugal
| | - Pedro Azevedo
- Cardiology Department, Centro Hospitalar Universitário do Algarve, Faro, Portugal.,Algarve Biomedical Center, Faro, Portugal
| | - Sandra Cunha
- Cardiology Department, Centro Hospitalar Universitário do Algarve, Faro, Portugal.,Algarve Biomedical Center, Faro, Portugal
| | - Dina Bento
- Cardiology Department, Centro Hospitalar Universitário do Algarve, Faro, Portugal.,Algarve Biomedical Center, Faro, Portugal.,Departamento de Ciências Biomédicas e Medicina, Universidade do Algarve, Faro, Portugal
| | - Nuno Marques
- Cardiology Department, Centro Hospitalar Universitário do Algarve, Faro, Portugal.,Algarve Biomedical Center, Faro, Portugal.,Departamento de Ciências Biomédicas e Medicina, Universidade do Algarve, Faro, Portugal
| | | | - Salomé Pereira
- Cardiology Department, Centro Hospitalar Universitário do Algarve, Faro, Portugal.,Algarve Biomedical Center, Faro, Portugal
| | - Ângelo Nobre
- Cardiothoracic Surgery Department, Centro Hospitalar Lisboa Norte, Lisboa, Portugal
| | - Ilídio de Jesus
- Cardiology Department, Centro Hospitalar Universitário do Algarve, Faro, Portugal.,Algarve Biomedical Center, Faro, Portugal
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12
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Jácome C, Pereira R, Almeida R, Amaral R, Correia MA, Mendes S, Vieira-Marques P, Ferreira JA, Lopes I, Gomes J, Vidal C, López Freire S, Méndez Brea P, Arrobas A, Valério M, Chaves Loureiro C, Santos LM, Couto M, Araujo L, Todo Bom A, Azevedo JP, Cardoso J, Emiliano M, Gerardo R, Lozoya C, Pinto PL, Castro Neves A, Pinto N, Palhinha A, Teixeira F, Ferreira-Magalhães M, Alves C, Coelho D, Santos N, Menezes F, Gomes R, Cidrais Rodrigues JC, Oliveira G, Carvalho J, Rodrigues Alves R, Moreira AS, Costa A, Abreu C, Silva R, Morête A, Falcão H, Marques ML, Câmara R, Cálix MJ, Bordalo D, Silva D, Vasconcelos MJ, Fernandes RM, Ferreira R, Freitas P, Lopes F, Almeida Fonseca J. Validation of App and Phone Versions of the Control of Allergic Rhinitis and Asthma Test (CARAT). J Investig Allergol Clin Immunol 2020; 31:270-273. [PMID: 32856596 DOI: 10.18176/jiaci.0640] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- C Jácome
- Center for Health Technology and Services Research (CINTESIS), Faculty of Medicine, University of Porto, Porto, Portugal.,Department of Community Medicine, Information and Health Decision Sciences (MEDCIDS), Faculty of Medicine, University of Porto, Porto, Portugal
| | - R Pereira
- Department of Community Medicine, Information and Health Decision Sciences (MEDCIDS), Faculty of Medicine, University of Porto, Porto, Portugal.,Allergy Unit, Instituto and Hospital CUF, Porto, Portugal
| | - R Almeida
- Center for Health Technology and Services Research (CINTESIS), Faculty of Medicine, University of Porto, Porto, Portugal.,Department of Community Medicine, Information and Health Decision Sciences (MEDCIDS), Faculty of Medicine, University of Porto, Porto, Portugal
| | - R Amaral
- Center for Health Technology and Services Research (CINTESIS), Faculty of Medicine, University of Porto, Porto, Portugal.,Dept. of Cardiovascular and Respiratory Sciences, Porto Health School, Polytechnic Institute of Porto, Porto, Portugal
| | - M A Correia
- Allergy Unit, Instituto and Hospital CUF, Porto, Portugal
| | - S Mendes
- Center for Health Technology and Services Research (CINTESIS), Faculty of Medicine, University of Porto, Porto, Portugal
| | - P Vieira-Marques
- Center for Health Technology and Services Research (CINTESIS), Faculty of Medicine, University of Porto, Porto, Portugal
| | - J A Ferreira
- Serviço de Imunoalergologia, Centro Hospitalar Vila Nova de Gaia/Espinho, Vila Nova de Gaia, Portugal
| | - I Lopes
- Serviço de Imunoalergologia, Centro Hospitalar Vila Nova de Gaia/Espinho, Vila Nova de Gaia, Portugal
| | - J Gomes
- Serviço de Imunoalergologia, Centro Hospitalar Vila Nova de Gaia/Espinho, Vila Nova de Gaia, Portugal
| | - C Vidal
- Servicio de Alergia, Complejo Hospitalario Universitario de Santiago, Santiago De Compostela, Spain
| | - S López Freire
- Servicio de Alergia, Complejo Hospitalario Universitario de Santiago, Santiago De Compostela, Spain
| | - P Méndez Brea
- Servicio de Alergia, Complejo Hospitalario Universitario de Santiago, Santiago De Compostela, Spain
| | - A Arrobas
- Serviço de Pneumologia, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal
| | - M Valério
- Serviço de Pneumologia, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal
| | - C Chaves Loureiro
- Serviço de Pneumologia, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal
| | - L M Santos
- Serviço de Pneumologia, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal
| | - M Couto
- Allergy Unit, Instituto and Hospital CUF, Porto, Portugal
| | - L Araujo
- Allergy Unit, Instituto and Hospital CUF, Porto, Portugal
| | - A Todo Bom
- Serviço de Imunoalergologia, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal
| | - J P Azevedo
- Imunoalergologia, Centro Hospitalar de Leiria, Leiria, Portugal
| | - J Cardoso
- Serviço de Pneumologia, Hospital Santa Marta, Centro Hospitalar Universitário de Lisboa Central, Lisboa, Portugal
| | - M Emiliano
- Serviço de Pneumologia, Hospital Santa Marta, Centro Hospitalar Universitário de Lisboa Central, Lisboa, Portugal
| | - R Gerardo
- Serviço de Pneumologia, Hospital Santa Marta, Centro Hospitalar Universitário de Lisboa Central, Lisboa, Portugal
| | - C Lozoya
- Serviço de Imunoalergologia, Hospital Amato Lusitano, Unidade Local de Saúde de Castelo Branco, Castelo Branco, Portugal
| | - P L Pinto
- Serviço de Imunoalergologia, Hospital de Dona Estefânia, Centro Hospitalar Universitário de Lisboa Central, Lisboa, Portugal
| | - A Castro Neves
- Serviço de Imunoalergologia, Hospital de Dona Estefânia, Centro Hospitalar Universitário de Lisboa Central, Lisboa, Portugal
| | - N Pinto
- Serviço de Imunoalergologia, Hospital de Dona Estefânia, Centro Hospitalar Universitário de Lisboa Central, Lisboa, Portugal
| | - A Palhinha
- Serviço de Imunoalergologia, Hospital de Dona Estefânia, Centro Hospitalar Universitário de Lisboa Central, Lisboa, Portugal
| | - F Teixeira
- Serviço de Pediatria, Centro Materno Infantil do Norte, Centro Hospitalar Universitário do Porto, Porto, Portugal
| | - M Ferreira-Magalhães
- Serviço de Pediatria, Centro Materno Infantil do Norte, Centro Hospitalar Universitário do Porto, Porto, Portugal
| | - C Alves
- Serviço de Pneumologia, Hospital Nossa Senhora do Rosário, Centro Hospitalar Barreiro Montijo, Barreiro, Portugal
| | - D Coelho
- Serviço de Pneumologia, Hospital Nossa Senhora do Rosário, Centro Hospitalar Barreiro Montijo, Barreiro, Portugal
| | - N Santos
- Serviço de Imunoalergologia, Centro Hospitalar Universitário do Algarve, Portimão, Portugal
| | - F Menezes
- Serviço de Pneumologia, Hospital Garcia de Orta, Almada, Portugal
| | - R Gomes
- Serviço de Pneumologia, Hospital Garcia de Orta, Almada, Portugal
| | - J C Cidrais Rodrigues
- Serviço de Pediatria, Hospital Pedro Hispano, Unidade Local de Saúde de Matosinhos, Matosinhos, Portugal
| | - G Oliveira
- Serviço de Pediatria, Hospital Pedro Hispano, Unidade Local de Saúde de Matosinhos, Matosinhos, Portugal
| | - J Carvalho
- Serviço de Pediatria, Hospital Pedro Hispano, Unidade Local de Saúde de Matosinhos, Matosinhos, Portugal
| | - R Rodrigues Alves
- Serviço de Imunoalergologia, Hospital do Divino Espirito Santo, Ponta Delgada, Portugal
| | - A S Moreira
- Serviço de Imunoalergologia, Hospital do Divino Espirito Santo, Ponta Delgada, Portugal
| | - A Costa
- Serviço de Pediatria, Hospital da Senhora da Oliveira, Guimarães, Portugal
| | - C Abreu
- Serviço de Imunoalergologia, Hospital São Pedro de Vila Real, Centro Hospitalar De Trás-Os-Montes E Alto Douro, Vila Real, Portugal
| | - R Silva
- Serviço de Imunoalergologia, Hospital São Pedro de Vila Real, Centro Hospitalar De Trás-Os-Montes E Alto Douro, Vila Real, Portugal
| | - A Morête
- Serviço de Imunoalergologia, Hospital Infante D. Pedro, Centro Hospitalar Baixo Vouga, Aveiro, Portugal
| | - H Falcão
- Serviço de Imunoalergologia, Centro Hospitalar Universitário do Porto, Porto, Portugal
| | - M L Marques
- Serviço de Imunoalergologia, Centro Hospitalar Universitário do Porto, Porto, Portugal
| | - R Câmara
- Serviço de Imunoalergologia, Serviço de Saúde da Região Autónoma da Madeira, Funchal, Portugal
| | - M J Cálix
- Serviço de Pediatria, Hospital de São Teotónio, Centro Hospitalar Tondela-Viseu, Viseu, Portugal
| | - D Bordalo
- Serviço de Pediatria, Unidade Hospitalar de Famalicão, Centro Hospitalar do Médio Ave, Vila Nova de Famalicão, Portugal
| | - D Silva
- Serviço de Imunoalergologia, Centro Hospitalar Universitário de São João, E.P.E., Porto, Portugal
| | - M J Vasconcelos
- Serviço de Imunoalergologia, Centro Hospitalar Universitário de São João, E.P.E., Porto, Portugal
| | - R M Fernandes
- Departamento de Pediatria, Hospital de Santa Maria, Centro Hospitalar Universitário Lisboa Norte, Lisboa, Portugal.,Farmacologia Clínica e Terapêutica, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - R Ferreira
- Departamento de Pediatria, Hospital de Santa Maria, Centro Hospitalar Universitário Lisboa Norte, Lisboa, Portugal.,Clínica Universitária de Pediatria, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - P Freitas
- Bloco operatório, Centro Hospitalar Vila Nova de Gaia/Espinho, Vila Nova de Gaia, Portugal
| | - F Lopes
- MEDIDA - Medicina, Educação, Investigação, Desenvolvimento e Avaliação, Porto, Portugal
| | - J Almeida Fonseca
- Center for Health Technology and Services Research (CINTESIS), Faculty of Medicine, University of Porto, Porto, Portugal.,Department of Community Medicine, Information and Health Decision Sciences (MEDCIDS), Faculty of Medicine, University of Porto, Porto, Portugal.,Allergy Unit, Instituto and Hospital CUF, Porto, Portugal.,MEDIDA - Medicina, Educação, Investigação, Desenvolvimento e Avaliação, Porto, Portugal
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13
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de Menezes GM, Almeida LA, Sander HH, Fernandes RM, Éckeli ÁL. 0942 Alternating Leg Muscle Activation and Hypnagogic Foot Tremor in Children: Comparative Study of Polysomnographic and Clinico-Demographic Variables. Sleep 2020. [DOI: 10.1093/sleep/zsaa056.938] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Introduction
The clinical and polysomnographic meaning of the Alternating Leg Muscle Activation (ALMA) and Hypnagogic Foot Tremor (HFT) patterns in children is not known.
Methods
A descriptive study was carried out to identify the prevalence and polysomnographic characteristics of ALMA and HFT sequences in a sample of 122 children sequentially admitted in the sleep laboratory, with the analysis of clinical and demographic characteristics of the ALMA/HFT group in relation to a comparison group without this condition, paired by age and gender.
Results
Sample prevalence was 14.8% for any HFT/ALMA event, 13.1% for ALMA and 10.7% for HFT. In the HFT/ALMA group, the mean age was 8 years old (2-12 years old), 66.7% of males. Obstructive Sleep Apnea was observed in 75% of children, but HFT / ALMA sequences only occasionally occurred in association with respiratory events. The use of medications with monoaminergic activity was associated with the occurrence of HFT/ALMA, p=0,019. There was higher N1 sleep content in the HFT / ALMA group, p=0,0301. There was no significant difference between both groups regarding the other clinical-demographic or polysomnographic parameters analyzed. Autonomic activation represented by heart rate fluctuations often occurred in association with the HFT / ALMA sequences, irrespective of the occurrence of arousals, awakenings, other motor or respiratory events.
Conclusion
HFT / ALMA is a frequent condition in children that are referred to the sleep lab.The stereotypy of the HFT / ALMA series suggests that their origin might be motor central pattern generators, which are potentially influenced by substances with monoaminergic effect. The finding of higher superficial sleep content in children with HFT / ALMA may indicate greater susceptibility to alteration of pediatric sleep architecture by such subtle motor events. The possibility of clinical consequences and cardiovascular diseases should be considered in relation to the association of HFT / ALMA with observed autonomic activation.
Support
None.
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Affiliation(s)
- G M de Menezes
- Ribeirao Preto Medical School - University of Sao Paulo, Ribeirão Preto - SP, BRAZIL
| | - L A Almeida
- Ribeirao Preto Medical School - University of Sao Paulo, Ribeirão Preto - SP, BRAZIL
| | - H H Sander
- Ribeirao Preto Medical School - University of Sao Paulo, Ribeirão Preto - SP, BRAZIL
| | - R M Fernandes
- Ribeirao Preto Medical School - University of Sao Paulo, Ribeirão Preto - SP, BRAZIL
| | - Á L Éckeli
- Ribeirao Preto Medical School - University of Sao Paulo, Ribeirão Preto - SP, BRAZIL
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14
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Merritt AM, Weber F, Castellan JP, Wolf T, Ishikawa D, Said AH, Alatas A, Fernandes RM, Baron AQR, Reznik D. Nematic Correlation Length in Iron-Based Superconductors Probed by Inelastic X-Ray Scattering. Phys Rev Lett 2020; 124:157001. [PMID: 32357044 DOI: 10.1103/physrevlett.124.157001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Accepted: 03/19/2020] [Indexed: 06/11/2023]
Abstract
Nematicity is ubiquitous in electronic phases of high-T_{c} superconductors, particularly in the Fe-based systems. We used inelastic x-ray scattering to extract the temperature-dependent nematic correlation length ξ from the anomalous softening of acoustic phonon modes in FeSe, underdoped Ba(Fe_{0.97}Co_{0.03})_{2}As_{2}, and optimally doped Ba(Fe_{0.94}Co_{0.06})_{2}As_{2}. In all cases, we find that ξ is well described by a power law (T-T_{0})^{-1/2} extending over a wide temperature range. Combined with the previously reported Curie-Weiss behavior of the nematic susceptibility, these results point to the mean-field character of the nematic transition, which we attribute to a sizable nematoelastic coupling that is likely detrimental to superconductivity.
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Affiliation(s)
- A M Merritt
- Department of Physics, University of Colorado at Boulder, Boulder, Colorado 80309, USA
| | - F Weber
- Institute for Solid State Physics, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
| | - J-P Castellan
- Institute for Solid State Physics, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
- CEA Saclay, Laboratoire Léon Brillouin, F-91191 Gif sur Yvette, France
| | - Th Wolf
- Institute for Solid State Physics, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
| | - D Ishikawa
- Materials Dynamics Laboratory, RIKEN SPring-8 Center, RIKEN, 1-1-1 Kouto, Sayo, Hyogo 679-5148 Japan
| | - A H Said
- Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - A Alatas
- Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - R M Fernandes
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - A Q R Baron
- Materials Dynamics Laboratory, RIKEN SPring-8 Center, RIKEN, 1-1-1 Kouto, Sayo, Hyogo 679-5148 Japan
| | - D Reznik
- Department of Physics, University of Colorado at Boulder, Boulder, Colorado 80309, USA
- Center for Experiments on Quantum Materials, University of Colorado at Boulder, Boulder, Colorado 80309, USA
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15
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Constant C, Cosme J, Fernandes RM, Fonte P, Fonseca JA, Alves C, Bandeira T. Practice of spirometry among physicians caring for children with asthma in Portugal - The EspiroPed survey. Pulmonology 2019; 26:54-56. [PMID: 31562046 DOI: 10.1016/j.pulmoe.2019.07.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 05/17/2019] [Accepted: 07/22/2019] [Indexed: 10/26/2022] Open
Affiliation(s)
- C Constant
- Unidade de Pneumologia Pediátrica, Departamento de Pediatria, Hospital de Santa Maria, Centro Hospitalar de Lisboa Norte, Centro Académico de Medicina de Lisboa.
| | - J Cosme
- Serviço de Imunoalergologia, Hospital de Santa Maria, CHLN EPE, Portugal
| | - R M Fernandes
- Unidade de Alergologia Pediátrica, Departamento de Pediatria, Hospital de Santa Maria, CHLN EPE, Centro Académico de Medicina de Lisboa, Lisboa, Portugal
| | - P Fonte
- Unidade de Saúde Familiar do Minho, ACeS Cávado I - Braga, Escola de Medicina/Instituto de Investigação em Ciências da Vida e Saúde, Universidade do Minho, Grupo de Estudos de Doenças Respiratórias, Associação Portuguesa de Medicina Geral e Familiar, Portugal
| | - J A Fonseca
- Imunoalergologia, CUF Porto Hospital e Instituto, CINTESIS, Faculdade de Medicina da Universidade do Porto, Sociedade Portuguesa de Alergologia e Imunologia Clínica, Portugal
| | - C Alves
- Serviço de Pneumologia, Hospital Nossa Senhora do Rosário, Centro Hospitalar Barreiro-Montijo, Sociedade Portuguesa de Pneumologia, Portugal
| | - T Bandeira
- Unidade de Pneumologia Pediátrica, Departamento de Pediatria, Hospital de Santa Maria, Centro Hospitalar de Lisboa Norte, Centro Académico de Medicina de Lisboa, Sociedade Portuguesa de Pediatria, Portugal
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16
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Rosa PFS, Thomas SM, Balakirev FF, Bauer ED, Fernandes RM, Thompson JD, Ronning F, Jaime M. Enhanced Hybridization Sets the Stage for Electronic Nematicity in CeRhIn_{5}. Phys Rev Lett 2019; 122:016402. [PMID: 31012717 DOI: 10.1103/physrevlett.122.016402] [Citation(s) in RCA: 2] [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: 03/14/2018] [Revised: 09/26/2018] [Indexed: 06/09/2023]
Abstract
High magnetic fields induce a pronounced in-plane electronic anisotropy in the tetragonal antiferromagnetic metal CeRhIn_{5} at H^{*}≳30 T for fields ≃20° off the c axis. Here we investigate the response of the underlying crystal lattice in magnetic fields to 45 T via high-resolution dilatometry. At low fields, a finite magnetic field component in the tetragonal ab plane explicitly breaks the tetragonal (C_{4}) symmetry of the lattice revealing a finite nematic susceptibility. A modest a-axis expansion at H^{*} hence marks the crossover to a fluctuating nematic phase with large nematic susceptibility. Magnetostriction quantum oscillations confirm a Fermi surface change at H^{*} with the emergence of new orbits. By analyzing the field-induced change in the crystal-field ground state, we conclude that the in-plane Ce 4f hybridization is enhanced at H^{*}, in agreement with the in-plane lattice expansion. We argue that the nematic behavior observed in this prototypical heavy-fermion material is of electronic origin, and is driven by the hybridization between 4f and conduction electrons which carries the f-electron anisotropy to the Fermi surface.
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Affiliation(s)
- P F S Rosa
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - S M Thomas
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - F F Balakirev
- National High Magnetic Field Laboratory, Los Alamos, New Mexico 87545, USA
| | - E D Bauer
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - R M Fernandes
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - J D Thompson
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - F Ronning
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - M Jaime
- National High Magnetic Field Laboratory, Los Alamos, New Mexico 87545, USA
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17
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Kissikov T, Sarkar R, Lawson M, Bush BT, Timmons EI, Tanatar MA, Prozorov R, Bud'ko SL, Canfield PC, Fernandes RM, Curro NJ. Uniaxial strain control of spin-polarization in multicomponent nematic order of BaFe 2As 2. Nat Commun 2018. [PMID: 29535323 PMCID: PMC5849640 DOI: 10.1038/s41467-018-03377-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The iron-based high temperature superconductors exhibit a rich phase diagram reflecting a complex interplay between spin, lattice, and orbital degrees of freedom. The nematic state observed in these compounds epitomizes this complexity, by entangling a real-space anisotropy in the spin fluctuation spectrum with ferro-orbital order and an orthorhombic lattice distortion. A subtle and less-explored facet of the interplay between these degrees of freedom arises from the sizable spin-orbit coupling present in these systems, which translates anisotropies in real space into anisotropies in spin space. We present nuclear magnetic resonance studies, which reveal that the magnetic fluctuation spectrum in the paramagnetic phase of BaFe2As2 acquires an anisotropic response in spin-space upon application of a tetragonal symmetry-breaking strain field. Our results unveil an internal spin structure of the nematic order parameter, indicating that electronic nematic materials may offer a route to magneto-mechanical control. A fundamental understanding of nematic order is one of the most important issues to explore in the high temperature superconductors. Here, the authors unveil an internal spin structure of the nematic order in BaFe2As2 by using nuclear magnetic resonance under precisely controlled tunable strain.
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Affiliation(s)
- T Kissikov
- Department of Physics, University of California, Davis, CA, 95616, USA
| | - R Sarkar
- Institute for Solid State Physics, TU Dresden, D-01069, Dresden, Germany
| | - M Lawson
- Department of Physics, University of California, Davis, CA, 95616, USA
| | - B T Bush
- Department of Physics, University of California, Davis, CA, 95616, USA
| | - E I Timmons
- Ames Laboratory U.S. DOE and Department of Physics and Astronomy, Iowa State University, Ames, IA, 50011, USA
| | - M A Tanatar
- Ames Laboratory U.S. DOE and Department of Physics and Astronomy, Iowa State University, Ames, IA, 50011, USA
| | - R Prozorov
- Ames Laboratory U.S. DOE and Department of Physics and Astronomy, Iowa State University, Ames, IA, 50011, USA
| | - S L Bud'ko
- Ames Laboratory U.S. DOE and Department of Physics and Astronomy, Iowa State University, Ames, IA, 50011, USA
| | - P C Canfield
- Ames Laboratory U.S. DOE and Department of Physics and Astronomy, Iowa State University, Ames, IA, 50011, USA
| | - R M Fernandes
- School of Physics and Astronomy, University of Minnesota, Minneapolis, MN, 55455, USA
| | - N J Curro
- Department of Physics, University of California, Davis, CA, 95616, USA.
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18
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Tanatar MA, Böhmer AE, Timmons EI, Schütt M, Drachuck G, Taufour V, Kothapalli K, Kreyssig A, Bud'ko SL, Canfield PC, Fernandes RM, Prozorov R. Origin of the Resistivity Anisotropy in the Nematic Phase of FeSe. Phys Rev Lett 2016; 117:127001. [PMID: 27689292 DOI: 10.1103/physrevlett.117.127001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2015] [Indexed: 06/06/2023]
Abstract
The in-plane resistivity anisotropy is studied in strain-detwinned single crystals of FeSe. In contrast to other iron-based superconductors, FeSe does not develop long-range magnetic order below the tetragonal-to-orthorhombic transition at T_{s}≈90 K. This allows for the disentanglement of the contributions to the resistivity anisotropy due to nematic and magnetic orders. Comparing direct transport and elastoresistivity measurements, we extract the intrinsic resistivity anisotropy of strain-free samples. The anisotropy peaks slightly below T_{s} and decreases to nearly zero on cooling down to the superconducting transition. This behavior is consistent with a scenario in which the in-plane resistivity anisotropy is dominated by inelastic scattering by anisotropic spin fluctuations.
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Affiliation(s)
- M A Tanatar
- Ames Laboratory, Ames, Iowa 50011, USA
- Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA
| | | | - E I Timmons
- Ames Laboratory, Ames, Iowa 50011, USA
- Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA
| | - M Schütt
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - G Drachuck
- Ames Laboratory, Ames, Iowa 50011, USA
- Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA
| | - V Taufour
- Ames Laboratory, Ames, Iowa 50011, USA
| | - K Kothapalli
- Ames Laboratory, Ames, Iowa 50011, USA
- Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA
| | - A Kreyssig
- Ames Laboratory, Ames, Iowa 50011, USA
- Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA
| | - S L Bud'ko
- Ames Laboratory, Ames, Iowa 50011, USA
- Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA
| | - P C Canfield
- Ames Laboratory, Ames, Iowa 50011, USA
- Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA
| | - R M Fernandes
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - R Prozorov
- Ames Laboratory, Ames, Iowa 50011, USA
- Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA
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19
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Dioguardi AP, Kissikov T, Lin CH, Shirer KR, Lawson MM, Grafe HJ, Chu JH, Fisher IR, Fernandes RM, Curro NJ. NMR Evidence for Inhomogeneous Nematic Fluctuations in BaFe_{2}(As_{1-x}P_{x})_{2}. Phys Rev Lett 2016; 116:107202. [PMID: 27015507 DOI: 10.1103/physrevlett.116.107202] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2015] [Indexed: 06/05/2023]
Abstract
We present evidence for nuclear spin-lattice relaxation driven by glassy nematic fluctuations in isovalent P-doped BaFe_{2}As_{2} single crystals. Both the ^{75}As and ^{31}P sites exhibit a stretched-exponential relaxation similar to the electron-doped systems. By comparing the hyperfine fields and the relaxation rates at these sites we find that the As relaxation cannot be explained solely in terms of magnetic spin fluctuations. We demonstrate that nematic fluctuations couple to the As nuclear quadrupolar moment and can explain the excess relaxation. These results suggest that glassy nematic dynamics are a common phenomenon in the iron-based superconductors.
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Affiliation(s)
- A P Dioguardi
- Department of Physics, University of California, Davis, California 95616, USA
| | - T Kissikov
- Department of Physics, University of California, Davis, California 95616, USA
| | - C H Lin
- Department of Physics, University of California, Davis, California 95616, USA
| | - K R Shirer
- Department of Physics, University of California, Davis, California 95616, USA
| | - M M Lawson
- Department of Physics, University of California, Davis, California 95616, USA
| | - H-J Grafe
- IFW Dresden, Institute for Solid State Research, P.O. Box 270116, D-01171 Dresden, Germany
| | - J-H Chu
- Department of Applied Physics and Geballe Laboratory for Advanced Materials, Stanford University, Stanford, California 94305, USA
- Stanford Institute of Energy and Materials Science, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | - I R Fisher
- Department of Applied Physics and Geballe Laboratory for Advanced Materials, Stanford University, Stanford, California 94305, USA
- Stanford Institute of Energy and Materials Science, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | - R M Fernandes
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - N J Curro
- Department of Physics, University of California, Davis, California 95616, USA
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20
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Santos MEP, Moura LHP, Mendes MB, Arcanjo DDR, Monção NBN, Araújo BQ, Lopes JAD, Silva-Filho JC, Fernandes RM, Oliveira RCM, Citó AMGL, Oliveira AP. Hypotensive and vasorelaxant effects induced by the ethanolic extract of the Mimosa caesalpiniifolia Benth. (Mimosaceae) inflorescences in normotensive rats. J Ethnopharmacol 2015; 164:120-128. [PMID: 25683301 DOI: 10.1016/j.jep.2015.02.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Revised: 01/29/2015] [Accepted: 02/04/2015] [Indexed: 06/04/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Caatinga is highly influenced by its seasonality. This species is endemic in the northeastern region, which is rich in plants with pharmacological potential. Many of these plants are used by the population and some of them have confirmed pharmacological properties. Mimosa caesalpiniifolia Benth. (Mimosaceae) is a native plant from northeastern Brazil׳s caatinga, popularly known as sabiá and cascudo. The tea from the inflorescence of this species is used by the population of the semi-arid for the treatment of hypertension, and the utilization of the plant bark for the staunching of bleedings and wound washing in order to prevent inflammation; also, the ingestion of the bark infusion is used in the treatment of bronchitis. However, its pharmacological effects and mechanisms of action have not yet been studied. The aim of the present study was to determine the effect of the ethanolic extract of M. caesalpiniifolia on the cardiovascular system in rats. MATERIAL AND METHODS In a study for the assessment of the hypotensive effect of the extract, the polyethylene catheters were inserted in the aorta artery and inferior vena cava for the measurement of the arterial pressure and heart rate. When intragastric administration was performed, only one catheter was implanted in the abdominal aorta. In studies for the vasorelaxant activity, mesenteric arterial rings (1-2mm) were used: they were kept in Tyrode׳s solution (95% O2 and 5% CO2) and submitted to tension of 0.75 g/f for 1h. The results were expressed as mean ± S.E.M., significant to the values of p<0.05. RESULTS The administration of the doses through venous pathway (6.25; 12.5 and 25mg/kg, i.v.) promoted hypotension followed by bradycardia in the higher doses. The pre-treatment with atropine (2mg/kg, i.v.) interrupted both the hypotension and the bradycardia; with hexamethonium, hypotension was reverted and bradycardia was attenuated. While the administration of tea/flowers (25mg/kg i.v.) also promoted a following section of hypotension, a slight increase in heart rate was observed. When administered orally, MC-EtOH/flowers (100mg/kg, v.o.) promoted a decrease in the arterial pressure from 90 min on, without a significant alteration in the heart rate in relation to the control. In the in vitro study, a pharmacological trial was performed with the extracts obtained from parts of the species M. caesalpiifolia (leaves, bark, fruit and inflorescences). Among all extracts tested, the ethanolic extract from the inflorescences (MC-EtOH/flowers) presented higher vasorelaxant potency in relation to the other parts of the plant. Henceforth, MC-EtOH/flowers was used in the sequence. In mesenteric preparations pre-contracted with phenylephrine (10(-5)M), the MC-EtOH/flowers (0.1-750 µg/ml) promoted vasorelaxant effect regardless of the vascular endothelium. MC-EtOH/flowers inhibited the contractions induced by the cumulative addition of phenylephrine (10(-9)-10(-5)mol/l) or CaCl2 (10(-6)-3 × 10(-2)M), in a concentration-dependent way. In contractions induced by S(-)Bay K 8644, a Cav-L activator, the MC-EtOH/flowers promoted concentration-dependent relaxation, corroborating previous results. CONCLUSION The tea of flowers of M. caesalpiniifolia promotes hypotension and tachycardia, whereas ethanolic extract (MC-EtOH) promotes hypotension and bradycardia involving the participation of the muscarinic and ganglionic pathways, as well as vasorelaxant action involving the Ca(2+) influx inhibition blockade.
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Affiliation(s)
- M E P Santos
- Medicinal Plants Research Center, Federal University of Piauí, 64049-550 Terezina, PI, Brazil
| | - L H P Moura
- Medicinal Plants Research Center, Federal University of Piauí, 64049-550 Terezina, PI, Brazil
| | - M B Mendes
- Medicinal Plants Research Center, Federal University of Piauí, 64049-550 Terezina, PI, Brazil
| | - D D R Arcanjo
- Medicinal Plants Research Center, Federal University of Piauí, 64049-550 Terezina, PI, Brazil
| | - N B N Monção
- Department of Chemistry, Federal University of Piauí, 64049-550 Terezina, PI, Brazil
| | - B Q Araújo
- Department of Chemistry, Federal University of Piauí, 64049-550 Terezina, PI, Brazil
| | - J A D Lopes
- Department of Chemistry, Federal University of Piauí, 64049-550 Terezina, PI, Brazil
| | - J C Silva-Filho
- Medicinal Plants Research Center, Federal University of Piauí, 64049-550 Terezina, PI, Brazil
| | - R M Fernandes
- Department of Veterinary Medicine, Federal University of Piauí, 64049-550, Terezina, PI, Brazil
| | - R C M Oliveira
- Medicinal Plants Research Center, Federal University of Piauí, 64049-550 Terezina, PI, Brazil
| | - A M G L Citó
- Department of Chemistry, Federal University of Piauí, 64049-550 Terezina, PI, Brazil
| | - A P Oliveira
- Medicinal Plants Research Center, Federal University of Piauí, 64049-550 Terezina, PI, Brazil.
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21
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Arguello CJ, Rosenthal EP, Andrade EF, Jin W, Yeh PC, Zaki N, Jia S, Cava RJ, Fernandes RM, Millis AJ, Valla T, Osgood RM, Pasupathy AN. Quasiparticle interference, quasiparticle interactions, and the origin of the charge density wave in 2H-NbSe2. Phys Rev Lett 2015; 114:037001. [PMID: 25659014 DOI: 10.1103/physrevlett.114.037001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Indexed: 06/04/2023]
Abstract
We show that a small number of intentionally introduced defects can be used as a spectroscopic tool to amplify quasiparticle interference in 2H-NbSe2 that we measure by scanning tunneling spectroscopic imaging. We show, from the momentum and energy dependence of the quasiparticle interference, that Fermi surface nesting is inconsequential to charge density wave formation in 2H-NbSe2. We demonstrate that, by combining quasiparticle interference data with additional knowledge of the quasiparticle band structure from angle resolved photoemission measurements, one can extract the wave vector and energy dependence of the important electronic scattering processes thereby obtaining direct information both about the fermiology and the interactions. In 2H-NbSe2, we use this combination to confirm that the important near-Fermi-surface electronic physics is dominated by the coupling of the quasiparticles to soft mode phonons at a wave vector different from the charge density wave ordering wave vector.
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Affiliation(s)
- C J Arguello
- Department of Physics, Columbia University, New York, New York 10027, USA
| | - E P Rosenthal
- Department of Physics, Columbia University, New York, New York 10027, USA
| | - E F Andrade
- Department of Physics, Columbia University, New York, New York 10027, USA
| | - W Jin
- Department of Applied Physics and Applied Math, Columbia University, New York, New York 10027, USA
| | - P C Yeh
- Department of Applied Physics and Applied Math, Columbia University, New York, New York 10027, USA
| | - N Zaki
- Department of Electrical Engineering, Columbia University, New York, New York 10027, USA
| | - S Jia
- Department of Chemistry, Princeton University, Princeton, New Jersey 08540, USA
| | - R J Cava
- Department of Chemistry, Princeton University, Princeton, New Jersey 08540, USA
| | - R M Fernandes
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - A J Millis
- Department of Physics, Columbia University, New York, New York 10027, USA
| | - T Valla
- Brookhaven National Laboratory, Upton, New York 11973, USA
| | - R M Osgood
- Department of Electrical Engineering, Columbia University, New York, New York 10027, USA and Department of Chemistry, Princeton University, Princeton, New Jersey 08540, USA
| | - A N Pasupathy
- Department of Physics, Columbia University, New York, New York 10027, USA
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22
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Rosa PFS, Adriano C, Garitezi TM, Piva MM, Mydeen K, Grant T, Fisk Z, Nicklas M, Urbano RR, Fernandes RM, Pagliuso PG. Possible unconventional superconductivity in substituted BaFe2As2 revealed by magnetic pair-breaking studies. Sci Rep 2014; 4:6252. [PMID: 25176407 PMCID: PMC4150111 DOI: 10.1038/srep06252] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Accepted: 07/15/2014] [Indexed: 11/28/2022] Open
Abstract
The possible existence of a sign-changing gap symmetry in BaFe2As2-derived superconductors (SC) has been an exciting topic of research in the last few years. To further investigate this subject we combine Electron Spin Resonance (ESR) and pressure-dependent transport measurements to investigate magnetic pair-breaking effects on BaFe1.9M0.1As2 (M = Mn, Co, Cu, and Ni) single crystals. An ESR signal, indicative of the presence of localized magnetic moments, is observed only for M = Cu and Mn compounds, which display very low SC transition temperature (Tc) and no SC, respectively. From the ESR analysis assuming the absence of bottleneck effects, the microscopic parameters are extracted to show that this reduction of Tc cannot be accounted by the Abrikosov-Gorkov pair-breaking expression for a sign-preserving gap function. Our results reveal an unconventional spin- and pressure-dependent pair-breaking effect and impose strong constraints on the pairing symmetry of these materials.
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Affiliation(s)
- P F S Rosa
- 1] Instituto de Física "Gleb Wataghin", UNICAMP, Campinas-SP, 13083-859, Brazil [2] University of California, Irvine, California 92697-4574, USA
| | - C Adriano
- Instituto de Física "Gleb Wataghin", UNICAMP, Campinas-SP, 13083-859, Brazil
| | - T M Garitezi
- Instituto de Física "Gleb Wataghin", UNICAMP, Campinas-SP, 13083-859, Brazil
| | - M M Piva
- 1] Instituto de Física "Gleb Wataghin", UNICAMP, Campinas-SP, 13083-859, Brazil [2] Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, D-01187 Dresden, Germany
| | - K Mydeen
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, D-01187 Dresden, Germany
| | - T Grant
- University of California, Irvine, California 92697-4574, USA
| | - Z Fisk
- University of California, Irvine, California 92697-4574, USA
| | - M Nicklas
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, D-01187 Dresden, Germany
| | - R R Urbano
- Instituto de Física "Gleb Wataghin", UNICAMP, Campinas-SP, 13083-859, Brazil
| | - R M Fernandes
- School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455, USA
| | - P G Pagliuso
- Instituto de Física "Gleb Wataghin", UNICAMP, Campinas-SP, 13083-859, Brazil
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23
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Gallais Y, Fernandes RM, Paul I, Chauvière L, Yang YX, Méasson MA, Cazayous M, Sacuto A, Colson D, Forget A. Observation of incipient charge nematicity in Ba(Fe(1-x)Co(x))2As2. Phys Rev Lett 2013; 111:267001. [PMID: 24483810 DOI: 10.1103/physrevlett.111.267001] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Indexed: 06/03/2023]
Abstract
Using electronic Raman spectroscopy, we report direct measurements of charge nematic fluctuations in the tetragonal phase of strain-free Ba(Fe(1-x)Co(x))2As2 single crystals. The strong enhancement of the Raman response at low temperatures unveils an underlying charge nematic state that extends to superconducting compositions and which has hitherto remained unnoticed. Comparison between the extracted charge nematic susceptibility and the elastic modulus allows us to disentangle the charge contribution to the nematic instability, and to show that charge nematic fluctuations are weakly coupled to the lattice.
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Affiliation(s)
- Y Gallais
- Laboratoire Matériaux et Phénomenes Quantiques (UMR 7162 CNRS), Université Paris Diderot-Paris 7, Bâtiment Condorcet, 75205 Paris Cedex 13, France
| | - R M Fernandes
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - I Paul
- Laboratoire Matériaux et Phénomenes Quantiques (UMR 7162 CNRS), Université Paris Diderot-Paris 7, Bâtiment Condorcet, 75205 Paris Cedex 13, France
| | - L Chauvière
- Laboratoire Matériaux et Phénomenes Quantiques (UMR 7162 CNRS), Université Paris Diderot-Paris 7, Bâtiment Condorcet, 75205 Paris Cedex 13, France
| | - Y-X Yang
- Laboratoire Matériaux et Phénomenes Quantiques (UMR 7162 CNRS), Université Paris Diderot-Paris 7, Bâtiment Condorcet, 75205 Paris Cedex 13, France
| | - M-A Méasson
- Laboratoire Matériaux et Phénomenes Quantiques (UMR 7162 CNRS), Université Paris Diderot-Paris 7, Bâtiment Condorcet, 75205 Paris Cedex 13, France
| | - M Cazayous
- Laboratoire Matériaux et Phénomenes Quantiques (UMR 7162 CNRS), Université Paris Diderot-Paris 7, Bâtiment Condorcet, 75205 Paris Cedex 13, France
| | - A Sacuto
- Laboratoire Matériaux et Phénomenes Quantiques (UMR 7162 CNRS), Université Paris Diderot-Paris 7, Bâtiment Condorcet, 75205 Paris Cedex 13, France
| | - D Colson
- CEA-Saclay, IRAMIS, Service de Physique de l'Etat Condensé (SPEC URA CNRS 2464), F-91191 Gif-sur-Yvette, France
| | - A Forget
- CEA-Saclay, IRAMIS, Service de Physique de l'Etat Condensé (SPEC URA CNRS 2464), F-91191 Gif-sur-Yvette, France
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24
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Dhaka RS, Liu C, Fernandes RM, Jiang R, Strehlow CP, Kondo T, Thaler A, Schmalian J, Bud'ko SL, Canfield PC, Kaminski A. What controls the phase diagram and superconductivity in Ru-substituted BaFe2As2? Phys Rev Lett 2011; 107:267002. [PMID: 22243178 DOI: 10.1103/physrevlett.107.267002] [Citation(s) in RCA: 2] [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: 07/05/2011] [Indexed: 05/31/2023]
Abstract
We use high resolution angle-resolved photoemission to study the electronic structure of the iron based high-temperature superconductors Ba(Fe(1-x)Ru(x))(2)As(2) as a function of Ru concentration. We find that substitution of Ru for Fe is isoelectronic, i.e., it does not change the value of the chemical potential. More interestingly, there are no measured, significant changes in the shape of the Fermi surface or in the Fermi velocity over a wide range of substitution levels (0<x<0.55). Given that the suppression of the antiferromagnetic and structural phase is associated with the emergence of the superconducting state, Ru substitution must achieve this via a mechanism that does not involve changes of the Fermi surface. We speculate that this mechanism relies on magnetic dilution which leads to the reduction of the effective Stoner enhancement.
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Affiliation(s)
- R S Dhaka
- Division of Materials Science and Engineering, The Ames Laboratory, U.S. DOE and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA.
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25
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Fernandes RM, VanBebber LH, Bhattacharya S, Chandra P, Keppens V, Mandrus D, McGuire MA, Sales BC, Sefat AS, Schmalian J. Effects of nematic fluctuations on the elastic properties of iron arsenide superconductors. Phys Rev Lett 2010; 105:157003. [PMID: 21230930 DOI: 10.1103/physrevlett.105.157003] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2009] [Indexed: 05/30/2023]
Abstract
We demonstrate that the changes in the elastic properties of the FeAs systems, as seen in our resonant ultrasound spectroscopy data, can be naturally understood in terms of fluctuations of emerging nematic degrees of freedom. Both the softening of the lattice in the normal, tetragonal phase as well as its hardening in the superconducting phase are consistently described by our model. Our results confirm the view that structural order is induced by magnetic fluctuations.
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Affiliation(s)
- R M Fernandes
- Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA.
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26
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Nandi S, Kim MG, Kreyssig A, Fernandes RM, Pratt DK, Thaler A, Ni N, Bud'ko SL, Canfield PC, Schmalian J, McQueeney RJ, Goldman AI. Anomalous suppression of the orthorhombic lattice distortion in superconducting Ba(Fe1-xCox)2As2 single crystals. Phys Rev Lett 2010; 104:057006. [PMID: 20366790 DOI: 10.1103/physrevlett.104.057006] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2009] [Indexed: 05/29/2023]
Abstract
High-resolution x-ray diffraction measurements reveal an unusually strong response of the lattice to superconductivity in Ba(Fe1-xCox)2As2. The orthorhombic distortion of the lattice is suppressed and, for Co doping near x=0.063, the orthorhombic structure evolves smoothly back to a tetragonal structure. We propose that the coupling between orthorhombicity and superconductivity is indirect and arises due to the magnetoelastic coupling, in the form of emergent nematic order, and the strong competition between magnetism and superconductivity.
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Affiliation(s)
- S Nandi
- Ames Laboratory, U.S. DOE and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA
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27
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Palma P, Palma VL, Fernandes RM, Bohn A, Soares AMVM, Barbosa IR. Embryo-toxic effects of environmental concentrations of chlorpyrifos on the crustacean Daphnia magna. Ecotoxicol Environ Saf 2009; 72:1714-1718. [PMID: 19482356 DOI: 10.1016/j.ecoenv.2009.04.026] [Citation(s) in RCA: 11] [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] [Subscribe] [Scholar Register] [Received: 12/11/2008] [Revised: 04/20/2009] [Accepted: 04/25/2009] [Indexed: 05/27/2023]
Abstract
Chlorpyrifos is a non-systemic organophosphorus insecticide leading to the inhibition of the enzyme cholinesterase. Nowadays, this insecticide is widely used on a variety of crops and is frequently detected in surface waters around the world. The main aims of this study were to evaluate the effects of this insecticide on the embryonic development of Daphnia magna, and to assess the sensitivity of this endpoint in comparison with the endpoint of the chronic 21-day test. The featured endpoints were the number of offspring per female and abnormalities of both offspring and embryos. Chlorpyrifos exhibited significant toxic effects on the embryonic development manifested in the appearance of abnormalities, including arrested eggs, in 20% of the embryos exposed to a concentration of 0.01 microgL(-1). Furthermore, chronic exposition to the insecticide yielded a proportion of offspring abnormalities in later stages of development of about 43% at 0.01 microgL(-1). In contrast, a significant reduction in the number of offspring produced per female was only observed above a concentration of 0.03 microgL(-1). Hence, these results suggest that developmental abnormality was a more sensitive endpoint than the number of offspring production per female.
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Affiliation(s)
- P Palma
- Departamento de Ciências do Ambiente, Escola Superior Agrária de Beja, Beja 7800-295, Portugal.
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28
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Palma P, Palma VL, Matos C, Fernandes RM, Bohn A, Soares AMVM, Barbosa IR. Assessment of the pesticides atrazine, endosulfan sulphate and chlorpyrifos for juvenoid-related endocrine activity using Daphnia magna. Chemosphere 2009; 76:335-340. [PMID: 19403157 DOI: 10.1016/j.chemosphere.2009.03.059] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2009] [Revised: 03/23/2009] [Accepted: 03/27/2009] [Indexed: 05/27/2023]
Abstract
The water flea Daphnia magna belongs to the cyclical parthenogenic species, which can reproduce by either parthenogenesis or sexual reproduction. Recent studies have reported the involvement of the methylfarnesoate hormone, in male sex determination of D. magna. The aim of this study was to evaluate the juvenoid and anti-juvenoid activity of atrazine, endosulfan sulphate, and chlorpyrifos. To assess the juvenoid activity we exposed maternal daphnids to several concentrations of the respective pesticides, using the percentage of male production as endpoint. Fenoxycarb (1microgL(-1)) was used as a positive control. The anti-juvenoid activity was assessed using a similar bioassay after the addition of fenoxycarb (1microgL(-1)) to all test solutions. Fenoxycarb is an insect growth regulator that mimics the action of methylfarnesoate, and promoted the production of 95% of male offspring at the given concentration. Weak juvenoid-agonist activity was detected for endosulfan sulphate, with a significant increase of the percentage of male daphnids detected through logistic regression. In addition, atrazine and endosulfan sulphate antagonized the juvenoid activity of fenoxycarb. These results also corroborate the hypothesis that weak juvenoid agonists can simultaneously act as juvenoid antagonists as it has been observed in other hormonal systems.
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Affiliation(s)
- P Palma
- Departamento de Ciências do Ambiente, Escola Superior Agrária de Beja, 7800-295 Beja, Portugal.
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29
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Palma P, Kuster M, Alvarenga P, Palma VL, Fernandes RM, Soares AMVM, López de Alda MJ, Barceló D, Barbosa IR. Risk assessment of representative and priority pesticides, in surface water of the Alqueva reservoir (South of Portugal) using on-line solid phase extraction-liquid chromatography-tandem mass spectrometry. Environ Int 2009; 35:545-551. [PMID: 19010545 DOI: 10.1016/j.envint.2008.09.015] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2008] [Revised: 09/24/2008] [Accepted: 09/30/2008] [Indexed: 05/27/2023]
Abstract
Surface waters located in intensive agricultural areas are more vulnerable to the pesticides contamination, which is a major concern if the water is intended to be used for human consumption. The aim of this study was to evaluate the presence and the distribution of pesticides in the Alqueva reservoir, an important source of water supply (South of Portugal), considering their representativeness in the agricultural practice of the area. For the analysis of pesticides risk impact we used the environmental quality standards in the field of water policy proposed recently by the European Commission. The pesticides belonging to the classes of phenylureas, triazines, chloroacetanilides, organophosphorous and thiocarbamates were analysed by on-line solid phase extraction-liquid chromatography-tandem mass spectrometry. The pesticides more frequently detected were atrazine, simazine, diuron and terbuthylazine. The highest levels of these pesticides were registered in spring, after pesticides treatment, namely in olive-tree and vine crops. The priority pesticides atrazine and diuron reached values above the annual average proposed in the European Union Legislation. The herbicide atrazine reached values that surpassed the proposed maximum allowable concentration (2,000 ng L(-1)). The sampling stations most affected by these pesticides were Sra. Ajuda, Lucefecit and Alcarrache, located in the northern part of the reservoir, closer to Spain where the agricultural activity is more intensive.
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Affiliation(s)
- P Palma
- Departamento de Ciências do Ambiente, Escola Superior Agrária de Beja, Apartado 6158, 7801-908 Beja, Portugal.
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Alvarenga P, Palma P, Gonçalves AP, Fernandes RM, de Varennes A, Vallini G, Duarte E, Cunha-Queda AC. Organic residues as immobilizing agents in aided phytostabilization: (II) effects on soil biochemical and ecotoxicological characteristics. Chemosphere 2009; 74:1301-1308. [PMID: 19091381 DOI: 10.1016/j.chemosphere.2008.11.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2008] [Revised: 10/31/2008] [Accepted: 11/03/2008] [Indexed: 05/27/2023]
Abstract
Sewage sludge (SS), municipal solid waste compost, and garden waste compost (GWC) were used as immobilizing agents in aided phytostabilization of an acid metal-contaminated soil affected by mining activities. The organic residues were applied at 25, 50 and 100 Mg ha(-1) (dry weight basis) and perennial ryegrass (Lolium perenne L.) was used as a "green cover". We studied the effects of the treatments on soil phytotoxicity and enzymatic activities, and on the composition and toxicity of the soil leachate towards Vibrio fischeri and Daphnia magna. Application of SS led to the greatest values of dehydrogenase, acid phosphatase, beta-glucosidase, protease and urease activities, corresponding to the greatest overall microbial and biochemical activity in amended soils. Conversely, GWC did not increase these enzymatic activities, relative to the unamended soil, or enhance ryegrass growth. Cellulase activity increased with increasing application rates of the amendments tested, but decreased at the highest SS application rate. The organic amendments were able to suppress soil toxicity to levels that did not affect D. magna, when applied at 50 and 100 Mg ha(-1), but SS, at the same application rates, increased the soil leachate toxicity towards V. fischeri. Moreover, ryegrass showed some phytotoxic symptoms when 100 Mg ha(-1) of SS were applied. This study showed the importance of an integrated evaluation of soil quality on remediation processes. Although SS immobilized trace metals and corrected soil acidity, improving soil biochemical status, when used at high application rates it led to toxicity of soil leachate towards V. fischeri, decreased soil cellulase activity and impaired ryegrass growth.
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Affiliation(s)
- P Alvarenga
- Department of Environmental Sciences, Escola Superior Agrária de Beja, Apartado, Beja, Portugal.
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Alvarenga P, Gonçalves AP, Fernandes RM, de Varennes A, Vallini G, Duarte E, Cunha-Queda AC. Organic residues as immobilizing agents in aided phytostabilization: (I) effects on soil chemical characteristics. Chemosphere 2009; 74:1292-1300. [PMID: 19118864 DOI: 10.1016/j.chemosphere.2008.11.063] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2008] [Revised: 11/22/2008] [Accepted: 11/24/2008] [Indexed: 05/27/2023]
Abstract
A greenhouse experiment was conducted to evaluate the effect of three different organic residues, sewage sludge (SS), municipal solid waste compost (MSWC), and garden waste compost (GWC), as immobilizing agents in aided phytostabilization of a highly acidic metal-contaminated soil, affected by mining activities, using perennial ryegrass (Lolium perenne L.). The organic residues were applied at 25, 50 and 100 Mg ha(-1) (dry weight basis), and their effects on soil chemical characteristics and on relative plant growth and metal concentrations were assessed. All the organic residues tested immobilized Cu, Pb and Zn, decreasing their mobile fractions. This was corroborated by negative correlations obtained between mobile Cu, Pb and Zn and other soil chemical characteristics, which rose as a consequence of the amendments applied (i.e., pH, electrical conductivity, organic matter, nitrogen content, available P and available K), and by the multivariate exploratory techniques performed that showed an inverse correlation between these groups of variables. The greatest increase in ryegrass relative growth (more than three times) was obtained in the presence of 50 MgMS WC ha(-1), followed by SS at the same application dosage. GWC did not contribute to an increase in shoot growth, due to its small capacity to correct soil acidity and to supply essential macronutrients (N, P, K). No extractant was able of demonstrating by a linear correlation the uptake of Cu, Pb and Zn by ryegrass. This plant was therefore not a good "indicator" of Cu, Pb and Zn availability in the soil. The results obtained in this study suggest that ryegrass can be used in aided phytostabilization for this type of mine contaminated soils and that MSWC, and to a minor extent SS, applied at 50Mg ha(-1), were effective in the in situ immobilization of metals, improving soil chemical properties and leading to a large increase in plant biomass.
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Affiliation(s)
- P Alvarenga
- Department of Environmental Sciences, Escola Superior Agrária de Beja, Apartado, Beja, Portugal.
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Palma P, Palma VL, Matos C, Fernandes RM, Bohn A, Soares AMVM, Barbosa IR. Effects of atrazine and endosulfan sulphate on the ecdysteroid system of Daphnia magna. Chemosphere 2009; 74:676-681. [PMID: 19042009 DOI: 10.1016/j.chemosphere.2008.10.021] [Citation(s) in RCA: 20] [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] [Subscribe] [Scholar Register] [Received: 08/05/2008] [Revised: 09/29/2008] [Accepted: 10/15/2008] [Indexed: 05/27/2023]
Abstract
The ecdysteroid system is used by crustaceans and other arthropods as the major endocrine signalling molecules, regulating processes such as molting and embryonic development. The aim of this study was to evaluate the ecdysteroid activity of two pesticides (atrazine and endosulfan sulphate), with distinct modes of action and which act in the juvenoid system of the crustacean Daphnia magna as weak juvenoid compounds. To assess the ecdysteroid activity, we first exposed maternal daphnids and embryos to nominal concentrations of the pesticides and determined the effect promoted by these pesticides on the molting frequency and on abnormalities in the embryos development. Furthermore, we evaluated if the toxic effects observed with the isolated pesticides were promoted or not by the disruption of the ecdysteroids system of the crustacean, by co-administrating of them with 20-hydroxyecdysone hormone. This hormone is the prime form of the invertebrate's ecdysteroids system and it is responsible for the crustacean molting process. Both pesticides induced an increase of embryo abnormalities development. Endosulfan sulphate promoted a delay in the molting process. The effects induced by atrazine were not altered by co-exposure to 20-hydroxyecdysone. In contrast, the co-administration of 20-hydroxyecdysone allowed the reversion of the effects on both the molting process and embryonic development elicited by endosulfan sulphate. These results suggest that atrazine promotes its toxicity without interfering with the ecdysteroid activity of the crustacean. On the contrary, endosulfan sulphate is an anti-ecdysteroidal compound for D. magna.
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Affiliation(s)
- P Palma
- Departamento de Ciências do Ambiente, Escola Superior Agrária de Beja, Beja 7800-295, Portugal.
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Palma P, Palma VL, Fernandes RM, Soares AMVM, Barbosa IR. Endosulfan sulphate interferes with reproduction, embryonic development and sex differentiation in Daphnia magna. Ecotoxicol Environ Saf 2009; 72:344-350. [PMID: 18547642 DOI: 10.1016/j.ecoenv.2008.04.018] [Citation(s) in RCA: 11] [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] [Subscribe] [Scholar Register] [Received: 02/03/2008] [Revised: 04/23/2008] [Accepted: 04/26/2008] [Indexed: 05/26/2023]
Abstract
Endosulfan sulphate is the transformation product of endosulfan and it is the most frequent form of surface water contamination with endosulfan. The aim of this study was to evaluate the possible effects promoted by endosulfan sulphate in changes on the life cycle, embryo development and sex differentiation of Daphnia magna. The endpoints used were moulting frequency, fecundity, growth, developmentally abnormalities and sexual differentiation. The nominal concentrations of endosulfan sulphate tested ranged from 9.2 to 458.7 microg L(-1). Endosulfan sulphate promoted a significant decrease of the offspring number in all concentrations. Results showed a reduction of the size of females, together with a decrease in moulting frequency. Furthermore, an increase in embryo deformities was observed at all concentrations tested. Above a concentration of 91.7 microg L(-1) there was an increased production of males. The results suggest that endosulfan sulphate interferes with the life cycle and sex determination of the crustacean D. magna.
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Affiliation(s)
- P Palma
- Departamento de Ciências do Ambiente, Escola Superior Agrária de Beja, Beja 7800-295, Portugal.
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Alvarenga P, Gonçalves AP, Fernandes RM, de Varennes A, Vallini G, Duarte E, Cunha-Queda AC. Evaluation of composts and liming materials in the phytostabilization of a mine soil using perennial ryegrass. Sci Total Environ 2008; 406:43-56. [PMID: 18799197 DOI: 10.1016/j.scitotenv.2008.07.061] [Citation(s) in RCA: 15] [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] [Subscribe] [Scholar Register] [Received: 06/07/2008] [Revised: 07/31/2008] [Accepted: 07/31/2008] [Indexed: 05/04/2023]
Abstract
A microcosm experiment was carried out to evaluate the effects of municipal solid waste compost (MSWC) or garden waste compost (GWC), and liming materials in the rehabilitation of a soil affected by mining activities, and to study the use of perennial ryegrass (Lolium perenne L.) for phystostabilization. The performance of the amendments was assessed by soil chemical parameters, total and bioavailable metals (Cu, Pb and Zn), soil enzymatic activities, and plant relative growth and mineral composition. In general, both composts corrected soil acidity and increased the total organic matter content of the soil, although with a better performance in the case of MSWC, especially when considering total N and available P and K levels in the amended soil. The application of both composts and liming materials led to a decrease in the mobile fractions of Cu, Pb and Zn, but mobilisable fractions of Cu and Zn increased with MSWC application. Plant biomass increased more than three times in the presence of 50 Mg MSWC ha(-1) and with the combined use of 25 or 50 Mg MSWC ha(-1) and CaO, but no significant differences were observed when GWC was applied. Plant tissue analysis showed that the treatments did not significantly reduce Cu, Pb and Zn uptake by the plant. Dehydrogenase, and the enzymes related to the N-cycle, urease and protease, had increased activities with increasing MSWC application rate. Conversely, the enzymatic activities of both enzymes related to the C-cycle, cellulase and beta-glucosidase, were only positively affected by GWC application, a compost obtained from raw materials rich in C. Principal component analyses evidenced this clear separation between the effect of MSWC on soil enzymes related to the N-cycle and of GWC on soil enzymes related to the C-cycle. This study indicates that MSWC (50 Mg ha(-1), limed or unlimed) can be used successfully in the remediation of a highly acidic metal-contaminated soil, allowing the establishment of perennial ryegrass.
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Affiliation(s)
- P Alvarenga
- Department of Environmental Sciences, Escola Superior Agrária de Beja, Rua Pedro Soares, Apartado 6158, 7801-908 Beja, Portugal.
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Palma P, Palma VL, Fernandes RM, Soares AMVM, Barbosa IR. Acute toxicity of atrazine, endosulfan sulphate and chlorpyrifos to Vibrio fischeri, Thamnocephalus platyurus and Daphnia magna, relative to their concentrations in surface waters from the Alentejo region of Portugal. Bull Environ Contam Toxicol 2008; 81:485-9. [PMID: 18777155 DOI: 10.1007/s00128-008-9517-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2007] [Accepted: 08/20/2008] [Indexed: 05/16/2023]
Abstract
Ecotoxicological effects of the herbicide atrazine and the insecticides endosulfan sulphate and chlorpyrifos were evaluated using a test battery comprising aquatic organisms from different trophic levels. According to the categories established in the EU legislation, atrazine can be considered non-harmful for the species tested, while the insecticides can be considered very toxic for the crustaceans. The results of acute toxicity tests showed that the sensitivity of organisms were as follows: Thamnocephalus platyurus > Daphnia magna > Vibrio fischeri. Chlorpyrifos may act as a toxic compound in the aquatic environment of Guadiana River, as it may be detected in water at levels that promote toxic effects.
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Affiliation(s)
- P Palma
- Departamento de Ciências do Ambiente, Escola Superior Agrária de Beja, Beja 7800-295, Portugal.
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Alvarenga P, Palma P, Gonçalves AP, Baião N, Fernandes RM, de Varennes A, Vallini G, Duarte E, Cunha-Queda AC. Assessment of chemical, biochemical and ecotoxicological aspects in a mine soil amended with sludge of either urban or industrial origin. Chemosphere 2008; 72:1774-1781. [PMID: 18547605 DOI: 10.1016/j.chemosphere.2008.04.042] [Citation(s) in RCA: 12] [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] [Subscribe] [Scholar Register] [Received: 01/18/2008] [Revised: 04/14/2008] [Accepted: 04/15/2008] [Indexed: 05/26/2023]
Abstract
A greenhouse pot experiment was conducted to evaluate the effect of sewage sludge (SS), of sugar beet sludge (SBS), or of a combination of both, in the remediation of a highly acidic (pH 3.6) metal-contaminated soil, affected by mining activities. The SS was applied at 100 and 200 Mg ha(-1) (dry weight basis), and the SBS at 7 Mg ha(-1). All pots were sown with Italian ryegrass (Lolium multiflorum Lam.). After 60 d of growth, shoot biomass was quantified and analysed for Cu, Pb and Zn. The pseudo-total and bioavailable contents of Cu, Pb and Zn and the enzymatic activities of beta-glucosidase, acid phosphatase, cellulase, protease and urease were determined in the soil mixtures. Two indirect acute bioassays with leachates from the soil (luminescent inhibition of Vibrio fischeri and Daphnia magna immobilization) were also used. The SS, in particular when in combination with SBS, corrected soil acidity, while increasing the total organic matter content and the cation exchange capacity. The application of SS led to a decrease in the level of effective bioavailable metals (extracted by 0.01 M CaCl(2), pH 5.7, without buffer), but caused an increase in their potential bioavailability (extracted by a solution of 0.5M NH(4)CH(3)COO, 0.5 M CH(3)COOH and 0.01 M EDTA, pH 4.7). Plant biomass increased more than 10 times in the presence of 100 Mg SS ha(-1), and more than five times with the combined use of 100 Mg SS ha(-1) and SBS, but a considerable phytotoxic effect was observed for the application rate of 200 Mg SS ha(-1). Copper, Pb and Zn concentrations in the shoots of L. multiflorum decreased significantly when using 100 Mg SS ha(-1) or SBS. The activities of beta-glucosidase, urease and protease increased with increasing SS applications rates, but cellulase had a reduced activity when using 200 Mg ha(-1)SS. Both amendments were able to suppress soil toxicity to levels that did not affect D. magna, but increased the soil leachate toxicity towards V. fischeri, especially with the application of 200 Mg SS ha(-1). This study showed that for this type of mine soils, and when using SS of similar composition, the maximum SS application rate should be 100 Mg ha(-1), and that liming the SS amended soil with SBS did not contribute to a further improvement in soil quality.
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Affiliation(s)
- P Alvarenga
- Department of Environmental Sciences, Escola Superior Agrária de Beja, Rua Pedro Soares, Apartado 6158, 7801-908 Beja, Portugal.
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Santiago AF, Fernandes RM, Santos BP, Assis FA, Oliveira RP, Carvalho CR, Faria AMC. Role of mesenteric lymph nodes and aging in secretory IgA production in mice. Cell Immunol 2008; 253:5-10. [PMID: 18632091 DOI: 10.1016/j.cellimm.2008.06.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2008] [Revised: 05/21/2008] [Accepted: 06/04/2008] [Indexed: 12/12/2022]
Abstract
Although it is known that Peyer's patches are the major inductive site for S-IgA production and B1 cells contribute to half of the IgA plasma cells detected in the gut lamina propria, the type of contribution of mesenteric lymph nodes to the process is still unclear. Cytokines such as TGF-beta, IL-10, IL-4, IL-5, and IL-6, are required to promote IgA class switching and IgA synthesis. Aging-related alterations in T and B cells and in cytokine production are already known. Some reports have also proposed that S-IgA production might be altered in aged animals. Herein, we investigated the role of MLN and aging in S-IgA production. Two- to 18-month-old BALB/c mice were used to evaluate aging-related alterations and MLN were removed to study its role in S-IgA production. We found that MLN are important, although not essential for S-IgA production. In addition, we showed that production of IgA-related cytokines are well preserved in MLN but not in PP of aged mice and that S-IgA levels are not affected by aging. Our results suggest that MLN may play a complementary role in S-IgA production mostly in aged animals.
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Affiliation(s)
- A F Santiago
- Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, 31270-901 Belo Horizonte, MG, Brazil
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Alvarenga P, Palma P, Gonçalves AP, Fernandes RM, de Varennes A, Vallini G, Duarte E, Cunha-Queda AC. Evaluation of tests to assess the quality of mine-contaminated soils. Environ Geochem Health 2008; 30:95-9. [PMID: 18246433 DOI: 10.1007/s10653-008-9147-z] [Citation(s) in RCA: 15] [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] [Subscribe] [Scholar Register] [Received: 10/13/2006] [Accepted: 05/18/2007] [Indexed: 05/21/2023]
Abstract
An acid metal-contaminated soil from the Aljustrel mining area (a pyrite mine located in SW Portugal in the Iberian Pyrite Belt) was subjected to chemical characterisation and total metal quantification (Cd, Cr, Cu, Ni, Pb and Zn). Water-soluble metals were determined and a sequential extraction procedure was used to investigate metal speciation. Two bioavailable metal fractions were determined: a mobile fraction and a mobilisable fraction. Soil ecotoxicity was studied using a battery of bioassays: plant growth test and seed germination with cress (Lepidium sativum L.), earthworm (Eisenia fetida) mortality, E. fetida avoidance behaviour, luminescent inhibition of Vibrio fischeri and Daphnia magna immobilisation. Although the total content of Cu, Zn and Pb in the soil was large (362, 245 and 1,250 mg/kg dry matter, respectively), these metals were mostly structurally bound (87% for Cu, 81% for Zn and 89% for Pb) and, therefore, scarcely bioavailable. Nonetheless, the D. magna immobilization test using soil leachate showed an EC50 (48 h) of 36.3% (v/v), and the luminescent inhibition of V. fischeri presented an EC20 (15 min) of 45.2% and an EC20 (30 min) of 10.7% (v/v), suggesting a considerable toxic effect. In the direct exposure bioassays, E. fetida avoided the mine soil at the highest concentrations (50%, 75% and 100% v/v). At the same soil concentrations, cress showed negligible growth. The results suggest the need to use a battery of toxicity tests, in conjunction with chemical methods, in order to assess the quality of mine-contaminated soils correctly.
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Affiliation(s)
- P Alvarenga
- Departamento de Ciências do Ambiente, Escola Superior Agrária de Beja, Rua Pedro Soares, Apartado 158, 7801-902 Beja, Portugal.
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Alvarenga P, Palma P, Gonçalves AP, Fernandes RM, Cunha-Queda AC, Duarte E, Vallini G. Evaluation of chemical and ecotoxicological characteristics of biodegradable organic residues for application to agricultural land. Environ Int 2007; 33:505-13. [PMID: 17188749 DOI: 10.1016/j.envint.2006.11.006] [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] [Subscribe] [Scholar Register] [Received: 02/23/2006] [Revised: 06/21/2006] [Accepted: 11/02/2006] [Indexed: 05/13/2023]
Abstract
The use of organic waste and compost as a source of organic matter and nutrients is a common practice to improve soil physico-chemical properties, meanwhile reducing the need for inorganic fertilisers. Official guidelines to assess sewage sludge and compost quality are mostly based on total metal content of these residues. Measurement of the total concentration of metals may be useful as a general index of contamination, but provides inadequate or little information about their bioavailability, mobility or toxicity when the organic residue is applied to the soil. However, ecotoxicity tests provide an integrated measure of bioavailability and detrimental effects of contaminants in the ecosystem. In the present study, three different types of biodegradable organic residues (BORs) have been considered: sewage sludge from municipal wastewater treatment (SS), compost from the organic fraction of unsorted municipal solid waste (MSWC), and garden waste compost (GWC). The BORs were subjected to chemical characterisation and total metal quantification (Cd, Cr, Cu, Ni, Pb and Zn), in order to verify their suitability for land application. Water leachability was determined through the DIN 38414-S4 method, while the modified BCR sequential extraction procedure was used for metal speciation. Ecotoxicity of the BORs was studied by direct and indirect bioassays. Direct toxicity bioassays were: plant growth tests with cress (Lepidium sativum L.) and barley (Hordeum vulgare L.), and earthworm (Eisenia fetida) mortality. On the other hand, indirect exposure bioassays, with leachate from the residues, took into account: luminescent bacteria (Vibrio fischeri), seed germination (L. sativum and H. vulgare) and Daphnia magna immobilization. As far as total metal concentration is concerned, with particular reference to Zn, SS resulted neither suitable for the use in agriculture nor compatible to be disposed of as an inert material into landfill, according to the Directive 1999/31/EC. Zinc in SS was mainly present in exchangeable form (28.5%), appearing as highly bioavailable. As a consequence, SS exhibited either high ecotoxicity effects with the indirect exposure bioassays or significant mortality with the earthworm bioassay. Total content of metals in MSWC allowed its classification as "stabilised biowaste", according to 2nd draft [DG Env.A.2. Working document of Biological treatment of biowaste - 2nd draft. Directorate-General Environment, Brussels, 12th February; 2001. accessed in:http://europa.eu.int/comm/environment/waste/facts_en.htm, at 10/09/2002] while leachate, on the basis of the concentration of these contaminants, could be classified as "inert waste". This residue showed significant ecotoxicity effects with direct exposure bioassays as well as with the luminescent bacteria bioassay. However, it resulted less toxic than SS. Finally, GWC could be classified as a Class 2 compost, with no detectable toxic effects on the organisms used in the bioassays, except for the luminescent bacteria. In this case, an EC(50) of 73.0% was observed. Considering the results, the use of a battery of toxicity test in conjunction with chemical analysis should be suggested, in order to correctly assess possible environmental risks deriving from disposal or land application of biodegradable organic residues.
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Affiliation(s)
- P Alvarenga
- Departamento de Ciências do Ambiente, Escola Superior Agrária de Beja, Rua Pedro Soares, Apartado 158, 7801-902 Beja, Portugal.
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Matsumoto W, Antunes RP, Orsi IA, Fernandes RM. Collarless metal ceramic fixed partial denture: a clinical report. Braz Dent J 2002; 12:215-8. [PMID: 11696922] [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: 02/22/2023] Open
Abstract
A case of a collarless metal ceramic fixed partial denture with preparations made at a slightly supragingival level is reported. The absence of the metal collar in the buccal portion of the abutments provides an excellent esthetic appearance. The use of a collarless metal ceramic fixed partial denture is a viable approach for restoring dentition where the esthetic quality is the primary concern.
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Affiliation(s)
- W Matsumoto
- Department of Dental Materials and Prosthesis, Faculty of Dentistry of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil.
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Abstract
OBJECTIVE To analyze the relationship between periodic lateralized epileptiform discharges (PLED) and status epilepticus (SE), to evaluate the relationship between mortality and periodic patterns, and to determine whether a stereotypic sequence of EEG patterns exists during human SE. METHODS The authors performed a prospective clinical and electrographic study comprising 62 episodes of SE, 55 patients, and 254 ictal/postictal EEG recordings. Serial daily EEG were obtained in all cases. RESULTS Partial SE was the predominant clinical type. Four distinct ictal EEG patterns were identified: intermittent EEG seizures (IES), merging EEG seizures (MES), continuous ictal discharges (CID), and periodic epileptiform discharges (PED) which could be lateralized (PLED) or bilateral (PBED). IES was the most common ictal pattern. In the same record, only one combination of ictal patterns was observed corresponding to an association of PLED or PBED and MES pattern. Serial EEG demonstrated that approximately one-third of SE resolved before the second EEG, another one-third persisted and maintained the same ictal pattern throughout the entire evolution, and the final one-third showed variable ictal EEG patterns. PLED were also unequivocally associated with epileptic seizures, and in some patients were the initial ictal pattern. CONCLUSION PLED can be an ictal pattern; and, in contrast to previous observations, no stereotyped sequence of ictal EEG patterns was found. PLED/PBED were not a terminal ictal pattern in every case, and outcome was more related to age and etiology than to specific ictal EEG patterns.
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Affiliation(s)
- E Garzon
- Department of Neurology, Ribeirão Preto School of Medicine, University of São Paulo, Brazil
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Fernandes RM, Carbonare SB, Carneiro-Sampaio MM, Trabulsi LR. Inhibition of enteroaggregative Escherichia coli adhesion to HEp-2 cells by secretory immunoglobulin A from human colostrum. Pediatr Infect Dis J 2001; 20:672-8. [PMID: 11465839 DOI: 10.1097/00006454-200107000-00007] [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] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Enteroaggregative Escherichia coli (EAEC) is an important agent of the persistent diarrhea among low socioeconomic level children in developing countries that may be associated with chronic undernourishment. Breast-feeding is effective in protecting infants against diarrhea and other infectious diseases. The aim of the study is to verify the ability of human colostrum to inhibit aggregative adhesion of EAEC to HEp-2 cells and the presence of antibodies reactive to antigenic fractions of EAEC in colostrum samples. METHODS Enzyme-linked immunosorbent assay, immunoblotting and adhesion assays of EAEC to HEp-2 cells were done with pooled or individual colostrum samples (n = 35). Assays were performed with a well-known EAEC strain, 044:H18 E. coli (strain 042). Colostral IgA was isolated by affinity chromatography in Sepharose anti-human alpha chain column. RESULTS Total colostrum and isolated IgA inhibited EAEC adhesion, and this ability was associated with the presence of IgA antibodies against a 15-kDa band, compatible with the subunits of aggregative adherence fimbrial adhesin II, characteristic of the 042 strain, absent in its plasmid-cured isogenic strain, that was used as control. Individual colostrum samples also inhibited adhesion, showed variable antibody titles against EAEC antigens in enzyme-linked immunosorbent assay and recognized many antigenic fractions in immunoblotting assays, including the 15-kDa band. CONCLUSIONS These results confirm that IgA from human colostrum inhibits adhesion of EAEC to HEp-2 cells and suggest that colostrum IgA antibodies reactive to EAEC antigens may play a role in protection of infants against diarrhea caused by these bacteria.
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Affiliation(s)
- R M Fernandes
- Department of Microbiology and Parasitology, Santa Maria Federal University, Brazil
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Leite JP, Terra-Bustamante VC, Fernandes RM, Santos AC, Chimelli L, Sakamoto AC, Assirati JA, Takayanagui OM. Calcified neurocysticercotic lesions and postsurgery seizure control in temporal lobe epilepsy. Neurology 2000; 55:1485-91. [PMID: 11094102 DOI: 10.1212/wnl.55.10.1485] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Several studies suggest that neurocysticercosis is the main cause of symptomatic epilepsy in developing countries. In such areas, calcified cysticercotic lesions (CCL) are frequently found in patients with complex partial seizures associated with hippocampal sclerosis (HS). The authors studied whether there are clinical and pathologic differences between HS patients with and without CCL. METHODS The authors determined the clinical and pathologic findings of 30 patients with HS and compared them with 32 patients with HS + CCL. Hippocampi from both groups were measured for fascia dentata Timm staining and cell density in hippocampal subfields. RESULTS In the HS + CCL group, single or multiple CCL were found in all lobes with no lobar predominance. An initial precipitating event occurred in 83.3% of HS and in 62.5% of HS + CCL. First complex partial seizure occurred at 10.1 years in HS and at 11.9 years in HS + CCL. No significant differences were found for fascia dentata Timm staining and hippocampal cell densities. Good postsurgery outcome (Engel I classification) did not differ between groups, with this result occurring in 76.6% of patients with HS and 81.2% of patients with HS + CCL. CONCLUSIONS The presence of CCL does not influence the clinical and pathologic profile of patients with hippocampal atrophy. Clinical histories and postsurgical outcomes were similar to those of patients with classic HS, suggesting that the CCL is probably, in this set of patients, a coincidental pathology and does not have a role in epileptogenesis.
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Affiliation(s)
- J P Leite
- Department of Neurology, University of São Paulo School of Medicine at Ribeirão Preto, Brazil.
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Abstract
IG 1, a temperate phage of Bacillus subtilis, is strongly induced from its lysogens by 6-(p-hydroxyphenylazo)-uracil, an azopyrimidine known as selectively inhibiting the B. subtilis DNA polymerase III. IG 1 phages originated either by induction or infection multiply, abundantly, in the presence of that azopyrimidine, in spite of the drastic decline of cell viability. Chloramphenicol completely suppresses the induction effect and also blocks the formation of spontaneously induced phage particles.
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Affiliation(s)
- R M Fernandes
- Faculdade de Ciencias e Tecnologia, Universidade Nova de Lisboa, Monte de Caparica, Portugal
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Abstract
A patient with ring 14 chromosome is reported. On the basis of this case and of a review of 28 cases published in the literature, the frequency of clinical signs and symptoms is determined, the constant and early incidence of epileptic seizures is emphasized and their characteristics are described. The associated congenital malformations are listed and their importance for karyotyping and consequent detection of new cases is emphasized.
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Affiliation(s)
- M H Duarte
- Departamento de Medicina, Especializada da Fundação Universidade de Brasília
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46
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Abstract
The temperate phages IG1, IG3, and IG4 of Bacillus subtilis were found to mediate specialized transduction of a lambda-like type. High frequency transducing lysates were also obtained. In many instances the transductants were shown to be heterogenotes, segregating the mutant alleles. They are presumably the result of transduction by addition. These findings are discussed together with data on other members of the group III of temperate bacteriophages aiming to a deeper understanding of that group, and of its evolutionary history.
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Affiliation(s)
- R M Fernandes
- Laboratório de Genética Molecular, Instituto Gulbenkian de Ciência, Oeiras, Portugal
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Fernandes RM, Roselino RB, Campos GM, Abraão W. [High temperature investments. 1. Evaluation of some physical properties]. Rev Odontol Univ Sao Paulo 1989; 3:253-7. [PMID: 2638487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
An evaluation of linear dimensional alterations of normal and hygroscopic setting of 3 phosphate-bonded investments and gypsum-bonded investments was made. The phosphate-bonded investments were processed with 100, 75, 50 and 25% special liquid. We investigated the maximum temperatures tolerated by the investments, in relation to the normal setting reactions. To evaluate expansion of normal and hygroscopic setting an electronic palpater was used, with the investments confined. The temperatures of the thermal reactions were detected by a digital thermometer. We confirmed that the CERAMIGOLD and HI-TEMP investments, processed with 75% special liquid, presented a greater linear expansion than the normal settings. The HI-HEAT presented less expansion than the normal setting and greater linear expansion than the hygroscopic setting. The MULTI-VEST tolerated the highest temperature during the evaluation.
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Moura-Ribeiro MV, Ferlin ML, Gallina RA, Funayama CA, Fernandes RM. [Non-ketotic hyperglycinemia. Study of a case]. Arq Neuropsiquiatr 1987; 45:67-71. [PMID: 3606438 DOI: 10.1590/s0004-282x1987000100009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Non-ketotic hyperglycinemia is one of inborn metabolic errors that manifest by epileptic seizures of difficult control from the first days of life in hypotonic newborn children. The lack of enzyme that catalyzes the conversion of glycine to hydroxymethyltetrahydrofolic acid, carbon dioxide and ammonia, in liver and brain, results in increased concentration of glycine in blood. It is reported in this study a case of non-ketotic hyperglycinemia diagnosed in neonatal period and characterized by hypotonia and non-controlled multiple seizures. The clinical and electroencephalographic findings, treatment as well as anatomopathologic study are discussed.
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Abstract
Three temperate bacteriophages of Bacillus subtilis were isolated from soil samples and analysed, together with all the other known temperate phages of this organism, with respect to their host range, immunity, serology and DNA restriction pattern, and by other tests. The results show that the newly isolated phages are new members of the immunity sub-group I of the group III of B. subtilis temperate bacteriophages. We named these new phages IG1, IG3 and IG4.
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