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Liphaus BL, Silva SC, Palmeira P, Silva CA, Goldenstein-Schainberg C, Carneiro-Sampaio M. Reduced expressions of apoptosis-related proteins TRAIL, Bcl-2, and TNFR1 in NK cells of juvenile-onset systemic lupus erythematosus patients: relations with disease activity, nephritis, and neuropsychiatric involvement. Front Immunol 2024; 15:1327255. [PMID: 38562920 PMCID: PMC10982494 DOI: 10.3389/fimmu.2024.1327255] [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] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Accepted: 03/04/2024] [Indexed: 04/04/2024] Open
Abstract
Background Lupus pathogenesis is mainly ascribed to increased production and/or impaired clearance of dead cell debris. Although self-reactive T and B lymphocytes are critically linked to lupus development, neutrophils, monocytes, and natural killer (NK) cells have also been implicated. This study assessed apoptosis-related protein expressions in NK cells of patients with juvenile-onset systemic lupus erythematosus (jSLE) and relations to disease activity parameters, nephritis, and neuropsychiatric involvement. Methods Thirty-six patients with jSLE, 13 juvenile dermatomyositis (JDM) inflammatory controls, and nine healthy controls had Fas, FasL, TRAIL, TNFR1, Bcl-2, Bax, Bim, and caspase-3 expressions in NK cells (CD3-CD16+CD56+) simultaneously determined by flow cytometry. Disease activity parameters included Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K) score, erythrocyte sedimentation rate, C-reactive protein level, anti-double strain DNA antibody level, complement fractions C3 and C4 levels. Results Patients with jSLE had a profile of significantly reduced expression of TRAIL, Bcl-2, and TNFR1 proteins in NK cells when compared to healthy controls. Similar profile was observed in patients with jSLE with active disease, positive anti-dsDNA, nephritis, and without neuropsychiatric involvement. Patients with jSLE with positive anti-dsDNA also had reduced expression of Bax in NK cells when compared healthy controls and to those with negative anti-dsDNA. Yet, patients with jSLE with negative anti-dsDNA had reduced mean fluorescence intensity (MFI) of Bim in NK cells compared to healthy controls. Patients with jSLE with nephritis also had reduced MFI of Fas in NK cells when compared to those without nephritis. In addition, in patients with jSLE, the proportion of FasL-expressing NK cells directly correlated with the SLEDAI-2K score (rs = 0.6, p = 0.002) and inversely correlated with the C3 levels (rs = -0.5, p = 0.007). Moreover, patients with jSLE had increased NK cell percentage and caspase-3 protein expression in NK cells when compared to JDM controls. Conclusion This study extends to NK cells an altered profile of TRAIL, Bcl-2, TNFR1, Fas, FasL, Bax, Bim, and caspase-3 proteins in patients with jSLE, particularly in those with active disease, positive anti-dsDNA, nephritis, and without neuropsychiatric involvement. This change in apoptosis-related protein expressions may contribute to the defective functions of NK cells and, consequently, to lupus development. The full clarification of the role of NK cells in jSLE pathogenesis may pave the way for new therapies like those of NK cell-based.
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Affiliation(s)
- Bernadete L. Liphaus
- Laboratory of Medical Investigation, Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil
- Pediatric Rheumatology Unit, Instituto da Criança, Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil
| | - Simone C. Silva
- Laboratory of Medical Investigation, Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil
| | - Patrícia Palmeira
- Laboratory of Medical Investigation, Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil
| | - Clovis A. Silva
- Pediatric Rheumatology Unit, Instituto da Criança, Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil
- Disciplina de Reumatologia, Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil
| | | | - Magda Carneiro-Sampaio
- Laboratory of Medical Investigation, Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil
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Ruano CA, Grafino M, Borba A, Pinheiro S, Fernandes O, Silva SC, Bilhim T, Moraes-Fontes MF, Irion KL. Multimodality imaging in connective tissue disease-related interstitial lung disease. Clin Radiol 2020; 76:88-98. [PMID: 32868089 DOI: 10.1016/j.crad.2020.07.035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Accepted: 07/28/2020] [Indexed: 11/18/2022]
Abstract
Interstitial lung disease is a well-recognised manifestation and a major cause of morbidity and mortality in patients with connective tissue diseases. Interstitial lung disease may arise in the context of an established connective tissue disease or be the initial manifestation of an otherwise occult autoimmune disorder. Early detection and characterisation are paramount for adequate patient management and require a multidisciplinary approach, in which imaging plays a vital role. Computed tomography is currently the imaging method of choice; however, other imaging techniques have recently been investigated, namely ultrasound, magnetic resonance imaging, and positron-emission tomography, with promising results. The aim of this review is to describe the imaging findings of connective tissue disease-related interstitial lung disease and explain the role of each imaging technique in diagnosis and disease characterisation.
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Affiliation(s)
- C A Ruano
- Radiology Department, Hospital de Santa Marta, Centro Hospitalar Universitário de Lisboa Central, Lisboa, Portugal; Radiology Department, Hospital da Luz, Lisboa, Portugal; NOVA Medical School, Universidade Nova de Lisboa, Lisboa, Portugal.
| | - M Grafino
- Pulmonology Department, Hospital da Luz, Lisboa, Portugal
| | - A Borba
- Pulmonology Department, Hospital de Santa Marta, Centro Hospitalar Universitário de Lisboa Central, Lisboa, Portugal
| | - S Pinheiro
- Autoimmune Disease Unit, Unidade de Doenças Auto-imunes/Serviço Medicina 3, Hospital de Santo António dos Capuchos, Centro Hospitalar Universitário de Lisboa Central, Lisboa, Portugal
| | - O Fernandes
- Radiology Department, Hospital de Santa Marta, Centro Hospitalar Universitário de Lisboa Central, Lisboa, Portugal; Radiology Department, Hospital da Luz, Lisboa, Portugal
| | - S C Silva
- Radiology Department, Hospital de São José, Centro Hospitalar Universitário de Lisboa Central, Lisboa, Portugal
| | - T Bilhim
- NOVA Medical School, Universidade Nova de Lisboa, Lisboa, Portugal; Interventional Radiology Unit, Hospital Curry Cabral, Centro Hospitalar Universitário de Lisboa Central, Lisboa, Portugal
| | - M F Moraes-Fontes
- Autoimmune Disease Unit, Unidade de Doenças Auto-imunes/Serviço Medicina 7.2, Hospital Curry Cabral, Centro Hospitalar Universitário de Lisboa Central, Lisboa, Portugal
| | - K L Irion
- Radiology Department, Manchester Royal Infirmary, Manchester, United Kingdom; University of Manchester, Division of Infection Immunity & Respiratory Medicine, School of Biological Sciences, Manchester, United Kingdom
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Aguiar VAP, Medina NH, Added N, Macchione ELA, Alberton SG, Leite AR, Aguirre FR, Ribas RV, Perego CC, Fagundes LM, Terassi JC, Brage JAP, Simões RF, Morais OB, Almeida EA, Joaquim PM, Souza MS, Cecotte AFM, Martins R, Duarte JG, Scarduelli VB, Allegro PRP, Escudeiro R, Leistenschneider E, Oliveira RAN, Servelo WA, Silva MT, Sarmento VE, Carreira CA, Abreu JC, Silva SC, Santos HC, Rodrigues CL, Assis RF, Silva TF, Tabacniks MH, Joaquim AS, Minas JHP, Kashinsky D, Guazzelli MA, Seixas LE, Finco S, Benevenutti F. SAFIIRA: A heavy-ion multi-purpose irradiation facility in Brazil. Rev Sci Instrum 2020; 91:053301. [PMID: 32486736 DOI: 10.1063/1.5138644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 04/10/2020] [Indexed: 06/11/2023]
Abstract
This work describes the new facility for applied nuclear physics at the University of Sao Paulo, mainly for irradiation of electronic devices. It is a setup composed of a quadrupole doublet for beam focusing/defocusing plus multiple scattering through gold foils to produce low intensity, large-area, and high-uniformity heavy-ion beams from 1H to 107Ag. Beam intensities can be easily adjusted from 102 particles cm2/s to hundreds of nA for an area as large as 2.0 cm2 and uniformity better than 90%. Its irradiation chamber has a high-precision motorized stage, and the system is controlled by a LabViewTM environment, allowing measurement automation. Design considerations and examples of use are presented.
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Affiliation(s)
- V A P Aguiar
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - N H Medina
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - N Added
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - E L A Macchione
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - S G Alberton
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - A R Leite
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - F R Aguirre
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - R V Ribas
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - C C Perego
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - L M Fagundes
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - J C Terassi
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - J A P Brage
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - R F Simões
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - O B Morais
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - E A Almeida
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - P M Joaquim
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - M S Souza
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - A F M Cecotte
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - R Martins
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - J G Duarte
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - V B Scarduelli
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - P R P Allegro
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - R Escudeiro
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - E Leistenschneider
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - R A N Oliveira
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - W A Servelo
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - M T Silva
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - V E Sarmento
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - C A Carreira
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - J C Abreu
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - S C Silva
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - H C Santos
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - C L Rodrigues
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - R F Assis
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - T F Silva
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - M H Tabacniks
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - A S Joaquim
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - J H P Minas
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - D Kashinsky
- Institute of Physics, University of Sao Paulo, 05508-090 São Paulo, Brazil
| | - M A Guazzelli
- Universitary Center of FEI, 09850-901 São Bernardo do Campo, Brazil
| | - L E Seixas
- Information Technology Center, 13069-901 Campinas, Brazil
| | - S Finco
- Information Technology Center, 13069-901 Campinas, Brazil
| | - F Benevenutti
- Federal University of Rio Grande do Sul, 91509-900 Porto Alegre, Brazil
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Pessôa MTC, Valadares JMM, Rocha SC, Silva SC, McDermott JP, Sánchez G, Varotti FP, Scavone C, Ribeiro RIMA, Villar JAFP, Blanco G, Barbosa LA. 21-Benzylidene digoxin decreases proliferation by inhibiting the EGFR/ERK signaling pathway and induces apoptosis in HeLa cells. Steroids 2020; 155:108551. [PMID: 31812624 PMCID: PMC7028499 DOI: 10.1016/j.steroids.2019.108551] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 10/30/2019] [Accepted: 12/02/2019] [Indexed: 12/12/2022]
Abstract
Cardiotonic steroids (CTS) are agents traditionally known for their capacity to bind to the Na,K-ATPase (NKA), affecting the ion transport and the contraction of the heart. Natural CTS have been shown to also have effects on cell signaling pathways. With the goal of developing a new CTS derivative, we synthesized a new digoxin derivative, 21-benzylidene digoxin (21-BD). Previously, we have shown that this compound binds to NKA and has cytotoxic actions on cancer, but not on normal cells. Here, we further studied the mechanisms of actions of 21-BD. Working with HeLa cells, we found that 21-BD decreases the basal, as well as the insulin stimulated proliferation. 21-BD reduces phosphorylation of the epidermal growth factor receptor (EGFR) and extracellular-regulated kinase (ERK), which are involved in pathways that stimulate cell proliferation. In addition, 21-BD promotes apoptosis, which is mediated by the translocation of Bax from the cytosol to mitochondria and the release of mitochondrial cytochrome c to the cytosol. 21-BD also activated caspases-8, -9 and -3, and induced the cleavage of poly (ADP-ribose) polymerase-1 (PARP-1). Altogether, these results show that the new compound that we have synthesized exerts cytotoxic actions on HeLa cells by inhibition of cell proliferation and the activation of both the extrinsic and intrinsic apoptotic pathways. These results support the relevance of the cardiotonic steroid scaffold as modulators of cell signaling pathways and potential agents for their use in cancer.
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Affiliation(s)
- Marco Túlio C Pessôa
- Laboratório de Bioquímica Celular, Universidade Federal de São João del-Rei (UFSJ) Campus Centro-Oeste Dona Lindu, Divinópolis, MG, Brazil
| | - Jéssica M M Valadares
- Laboratório de Bioquímica Celular, Universidade Federal de São João del-Rei (UFSJ) Campus Centro-Oeste Dona Lindu, Divinópolis, MG, Brazil
| | - Sayonarah C Rocha
- Laboratório de Bioquímica Celular, Universidade Federal de São João del-Rei (UFSJ) Campus Centro-Oeste Dona Lindu, Divinópolis, MG, Brazil
| | - Simone C Silva
- Laboratório de Síntese Orgânica e Nanoestruturas, Universidade Federal de São João del-Rei (UFSJ) Campus Centro-Oeste Dona Lindu, Divinópolis, MG, Brazil
| | - Jeff P McDermott
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center (KUMC), Kansas City, KS, USA
| | - Gladis Sánchez
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center (KUMC), Kansas City, KS, USA
| | - Fernando P Varotti
- Núcleo de Pesquisa em Química Biológica (NQBio), Universidade Federal de São João del-Rei (UFSJ) Campus Centro-Oeste Dona Lindu, Divinópolis, MG, Brazil
| | - Cristóforo Scavone
- Laboratório de Neurofarmacologia Molecular, Departamento de Farmacologia, Instituto de Ciências Biomédicas, Universidade de São Paulo (USP), São Paulo, SP, Brazil
| | - Rosy I M A Ribeiro
- Laboratório de Patologia Experimental, Universidade Federal de São João del-Rei (UFSJ) Campus Centro-Oeste Dona Lindu, Divinópolis, MG, Brazil
| | - José A F P Villar
- Laboratório de Síntese Orgânica e Nanoestruturas, Universidade Federal de São João del-Rei (UFSJ) Campus Centro-Oeste Dona Lindu, Divinópolis, MG, Brazil
| | - Gustavo Blanco
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center (KUMC), Kansas City, KS, USA
| | - Leandro A Barbosa
- Laboratório de Bioquímica Celular, Universidade Federal de São João del-Rei (UFSJ) Campus Centro-Oeste Dona Lindu, Divinópolis, MG, Brazil.
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5
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Silva SC, Murinello N, Alfarroba S, Santos AS, Calvinho P, Semedo L. Lung transplant complicated with unexpected neoplasm in explanted lungs: A difficult challenge to manage. Pulmonology 2019; 26:172-174. [PMID: 31732438 DOI: 10.1016/j.pulmoe.2019.10.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 10/08/2019] [Accepted: 10/14/2019] [Indexed: 10/25/2022] Open
Affiliation(s)
- S C Silva
- Centro Hospitalar Universitário de Lisboa Central, Lisboa, Portugal.
| | - N Murinello
- Centro Hospitalar Universitário de Lisboa Central, Lisboa, Portugal
| | - S Alfarroba
- Centro Hospitalar Universitário de Lisboa Central, Lisboa, Portugal
| | - A S Santos
- Centro Hospitalar Universitário de Lisboa Central, Lisboa, Portugal
| | - P Calvinho
- Centro Hospitalar Universitário de Lisboa Central, Lisboa, Portugal
| | - L Semedo
- Centro Hospitalar Universitário de Lisboa Central, Lisboa, Portugal
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de Souza Gonçalves B, de Moura Valadares JM, Alves SLG, Silva SC, Rangel LP, Cortes VF, Villar JAFP, Barbosa LA, de Lima Santos H. Evaluation of neuroprotective activity of digoxin and semisynthetic derivatives against partial chemical ischemia. J Cell Biochem 2019; 120:17108-17122. [PMID: 31310381 DOI: 10.1002/jcb.28971] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [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: 06/16/2018] [Revised: 03/29/2019] [Accepted: 04/08/2019] [Indexed: 02/06/2023]
Abstract
Recently, cardiotonic steroids (CTS) have been shown to lead to the activation of Na,K-ATPase at low concentrations in brain, promoting neuroprotection against ischemia. We report here the results of the use of digoxin and its semisynthetic derivatives BD-14, BD-15, and BD-16 against partial chemical ischemic induction followed by reperfusion in murine neuroblastoma cells neuro-2a (N2a). For chemical ischemic induction, sodium azide (5 mM) was used for 5 hours, and then reperfusion was induced for 24 hours. Na,K-ATPase activity and protein levels were analyzed in membrane preparation of N2a cells pretreated with the compounds (150 nM), in the controls and in induced chemical ischemia. In the Na,K-ATPase activity and protein levels assays, the steroids digoxin and BD-15 demonstrated a capacity to modulate the activity of the enzyme directly, increasing its levels of expression and activity. Oxidative parameters, such as superoxide dismutase (SOD) activity, lipid peroxidation (thiobarbituric acid reactive substance), glutathione peroxidase (GPx), glutathione (GSH) levels, hydrogen peroxide content, and the amount of free radicals (reactive oxygen species) during induced chemical ischemia were also evaluated. Regarding the redox state, lipid peroxidation, hydrogen peroxide content, and GPx activity, we have observed an increase in the chemical ischemic group, and a reduction in the groups treated with CTS. SOD activity increased in all treated groups when compared to control and GSH levels decreased when treated with sodium azide and did not change with CTS treatments. Regarding the lipid profile, we saw a decrease in the content of phospholipids and cholesterol in the chemical ischemic group, and an increase in the groups treated with CTS. In conclusion, the compounds used in this study demonstrate promising results, since they appear to promote neuroprotection in cells exposed to chemical ischemia.
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Affiliation(s)
- Bruno de Souza Gonçalves
- Laboratório de Bioquímica Celular, Universidade Federal de São João del Rei, Divinópolis, Minas Gerais, Brazil
| | | | - Silmara L G Alves
- Laboratório de Síntese Orgânica e Nanoestruturas, Universidade Federal de São João del Rei, Divinópolis, Minas Gerais, Brazil
| | - Simone C Silva
- Laboratório de Síntese Orgânica e Nanoestruturas, Universidade Federal de São João del Rei, Divinópolis, Minas Gerais, Brazil
| | - Luciana P Rangel
- Laboratório de Bioquímica Tumoral, Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Vanessa F Cortes
- Laboratório de Bioquímica Celular, Universidade Federal de São João del Rei, Divinópolis, Minas Gerais, Brazil
| | - José A F P Villar
- Laboratório de Síntese Orgânica e Nanoestruturas, Universidade Federal de São João del Rei, Divinópolis, Minas Gerais, Brazil
| | - Leandro A Barbosa
- Laboratório de Bioquímica Celular, Universidade Federal de São João del Rei, Divinópolis, Minas Gerais, Brazil
| | - Hérica de Lima Santos
- Laboratório de Bioquímica Celular, Universidade Federal de São João del Rei, Divinópolis, Minas Gerais, Brazil
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Santos LM, Rodrigues D, Alemi M, Silva SC, Ribeiro CA, Cardoso I. Resveratrol administration increases Transthyretin protein levels ameliorating AD features- importance of transthyretin tetrameric stability. Mol Med 2016; 22:597-607. [PMID: 27385446 DOI: 10.2119/molmed.2016.00124] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 06/29/2016] [Indexed: 12/21/2022] Open
Abstract
Previous in vivo work showed that resveratrol has beneficial effects in the AD pathology, resulting in increased expression of transthyretin (TTR). TTR binds Aβ peptide avoiding its aggregation and toxicity, and is reduced in the CSF and plasma, in AD. Further, resveratrol binds TTR, stabilizing the native TTR tetrameric structure. To further explore the mechanism of neuroprotection conferred by TTR in AD, resveratrol was administrated, in the diet, to 5-8 months old AD transgenic female mice carrying just one copy of the mouse TTR gene, for two months. Effects in brain Aβ burden were evaluated by immunohistochemistry, and in total brain Aβ levels by ELISA, showing a striking decrease in both parameters in treated animals. In addition, total brain LRP1 protein levels were increased in treated animals, although its gene expression was unaltered. To further understand the mechanism(s) underlying such improvement in AD features, we measured TTR plasma levels showing that TTR increased in resveratrol-treated mice, whereas liver TTR gene transcription was not altered. These results strengthen the stability hypothesis, which postulates that TTR is unstable in AD leading to accelerated clearance and lower levels. Therefore, resveratrol which stabilizes the TTR tetramer results in TTR normalized clearance, thus increasing the protein plasma levels. In turn, stabilized TTR binds more strongly to Aβ peptide, avoiding its aggregation. Our results represent a step forward to the understanding of the mechanism underlying TTR protection in AD and highlight the possibility of using TTR stabilization as a therapeutic target in AD.
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Affiliation(s)
- L M Santos
- IBMC - Instituto de Biologia Celular e Molecular.,i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal
| | - D Rodrigues
- IBMC - Instituto de Biologia Celular e Molecular.,i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal.,ESTSP - Department of Health Sciences, School of Allied Health Technologies, Polytechnic Institute of Porto, Portugal
| | - M Alemi
- IBMC - Instituto de Biologia Celular e Molecular.,i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal.,Faculdade de Medicina, Universidade do Porto, Porto, Portugal
| | - S C Silva
- IBMC - Instituto de Biologia Celular e Molecular.,i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal.,ESTSP - Department of Health Sciences, School of Allied Health Technologies, Polytechnic Institute of Porto, Portugal
| | - C A Ribeiro
- IBMC - Instituto de Biologia Celular e Molecular.,i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal
| | - I Cardoso
- IBMC - Instituto de Biologia Celular e Molecular.,i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal
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Silva SC, Baggio-Zappia GL, Brunialti MKC, Assunçao MSC, Azevedo LCP, Machado FR, Salomao R. Evaluation of Toll-like, chemokine, and integrin receptors on monocytes and neutrophils from peripheral blood of septic patients and their correlation with clinical outcomes. ACTA ACUST UNITED AC 2014; 47:384-93. [PMID: 24728213 PMCID: PMC4075306 DOI: 10.1590/1414-431x20143190] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [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: 04/25/2013] [Accepted: 02/10/2014] [Indexed: 11/21/2022]
Abstract
Recognition of pathogens is performed by specific receptors in cells of the innate immune system, which may undergo modulation during the continuum of clinical manifestations of sepsis. Monocytes and neutrophils play a key role in host defense by sensing and destroying microorganisms. This study aimed to evaluate the expression of CD14 receptors on monocytes; CD66b and CXCR2 receptors on neutrophils; and TLR2, TLR4, TLR5, TLR9, and CD11b receptors on both cell types of septic patients. Seventy-seven septic patients (SP) and 40 healthy volunteers (HV) were included in the study, and blood samples were collected on day zero (D0) and after 7 days of therapy (D7). Evaluation of the cellular receptors was carried out by flow cytometry. Expression of CD14 on monocytes and of CD11b and CXCR2 on neutrophils from SP was lower than that from HV. Conversely, expression of TLR5 on monocytes and neutrophils was higher in SP compared with HV. Expression of TLR2 on the surface of neutrophils and that of TLR5 on monocytes and neutrophils of SP was lower at D7 than at D0. In addition, SP who survived showed reduced expression of TLR2 and TLR4 on the surface of neutrophils at D7 compared to D0. Expression of CXCR2 for surviving patients was higher at follow-up compared to baseline. We conclude that expression of recognition and cell signaling receptors is differentially regulated between SP and HV depending on the receptor being evaluated.
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Affiliation(s)
- S C Silva
- Disciplina de Infectologia, Departamento de Medicina, Hospital São Paulo, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brasil
| | - G L Baggio-Zappia
- Disciplina de Infectologia, Departamento de Medicina, Hospital São Paulo, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brasil
| | - M K C Brunialti
- Disciplina de Infectologia, Departamento de Medicina, Hospital São Paulo, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brasil
| | - M S C Assunçao
- Unidade de Terapia Intensiva, Hospital Israelita Albert Einstein, São Paulo, SP, Brasil
| | - L C P Azevedo
- Unidade de Terapia Intensiva, Hospital Sírio Libanês, São Paulo, SP, Brasil
| | - F R Machado
- Disciplina de Anestesiologia, Departamento de Cirurgia, Hospital São Paulo, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brasil
| | - R Salomao
- Disciplina de Infectologia, Departamento de Medicina, Hospital São Paulo, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brasil
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9
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Silva SC, Baggio-Zappia GL, Brunialti MKC, Silva E, Azevedo LCP, Machado FR, Salomao R. Evaluation of recognition and signalling receptors on the peripheral blood cells of septic patients and their correlation with clinical outcomes. Crit Care 2013. [PMCID: PMC3891453 DOI: 10.1186/cc12664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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10
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Périgo EA, Silva SC, de Sousa EMB, Freitas AA, Cohen R, Nagamine LCCM, Takiishi H, Landgraf FJG. Properties of nanoparticles prepared from NdFeB-based compound for magnetic hyperthermia application. Nanotechnology 2012; 23:175704. [PMID: 22481311 DOI: 10.1088/0957-4484/23/17/175704] [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] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Nanoparticles were prepared from a NdFeB-based alloy using the hydrogen decrepitation process together with high-energy ball milling and tested as heating agent for magnetic hyperthermia. In the milling time range evaluated (up to 10 h), the magnetic moment per mass at H = 1.59 MA m(-1) is superior than 70 A m(2) kg(-1); however, the intrinsic coercivity might be inferior than 20 kA m(-1). The material presents both ferromagnetic and superparamagnetic particles constituted by a mixture of phases due to the incomplete disproportionation reaction of Nd(2)Fe(14)BH(x) during milling. Solutions prepared with deionized water and magnetic particles exposed to an AC magnetic field (H(max) ~ 3.7 kA m(-1) and f = 228 kHz) exhibited 26 K ≤ ΔT(max) ≤ 44 K with a maximum estimated specific absorption rate (SAR) of 225 W kg(-1). For the pure magnetic material milled for the longest period of time (10 h), the SAR was estimated as ~2500 W kg(-1). In vitro tests indicated that the powders have acceptable cytotoxicity over a wide range of concentration (0.1-100 µg ml(-1)) due to the coating applied during milling.
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Affiliation(s)
- E A Périgo
- Center for Process and Product Technology, Institute of Technological Research, São Paulo, SP 05508-901, Brazil.
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11
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Silva SC, Brum MCS, Weiblen R, Flores EF, Chowdhury SI. A bovine herpesvirus 5 recombinant defective in the thymidine kinase (TK) gene and a double mutant lacking TK and the glycoprotein E gene are fully attenuated for rabbits. Braz J Med Biol Res 2009; 43:150-9. [PMID: 20027480 DOI: 10.1590/s0100-879x2009007500030] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2009] [Accepted: 12/10/2009] [Indexed: 05/26/2023] Open
Abstract
Bovine herpesvirus 5 (BoHV-5), the agent of herpetic meningoencephalitis in cattle, is an important pathogen of cattle in South America and several efforts have been made to produce safer and more effective vaccines. In the present study, we investigated in rabbits the virulence of three recombinant viruses constructed from a neurovirulent Brazilian BoHV-5 strain (SV507/99). The recombinants are defective in glycoprotein E (BoHV-5gEDelta), thymidine kinase (BoHV-5TKDelta) and both proteins (BoHV-5gEDeltaTKDelta). Rabbits inoculated with the parental virus (N = 8) developed neurological disease and died or were euthanized in extremis between days 7 and 13 post-infection (pi). Infectivity was detected in several areas of their brains. Three of 8 rabbits inoculated with the recombinant BoHV-5gEDelta developed neurological signs between days 10 and 15 pi and were also euthanized. A more restricted virus distribution was detected in the brain of these animals. Rabbits inoculated with the recombinants BoHV-5TKDelta (N = 8) or BoHV-5gEDeltaTKDelta (N = 8) remained healthy throughout the experiment in spite of variable levels of virus replication in the nose. Dexamethasone (Dx) administration to rabbits inoculated with the three recombinants at day 42 pi did not result in viral reactivation, as demonstrated by absence of virus shedding and/or increase in virus neutralizing titers. Nevertheless, viral DNA was detected in the trigeminal ganglia or olfactory bulbs of all animals at day 28 post-Dx, demonstrating they were latently infected. These results show that recombinants BoHV-5TKDelta and BoHV-5gEDeltaTKDelta are attenuated for rabbits and constitute potential vaccine candidates upon the confirmation of this phenotype in cattle.
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Affiliation(s)
- S C Silva
- Setor de Virologia, Departamento de Microbiologia e Parasitologia and Departamento de Medicina Veterinária Preventiva, Universidade Federal de Santa Maria, Santa Maria, RS, Brasil
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12
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Callegaro CC, Moraes RS, Negrão CE, Trombetta IC, Rondon MU, Teixeira MS, Silva SC, Ferlin EL, Krieger EM, Ribeiro JP. Acute water ingestion increases arterial blood pressure in hypertensive and normotensive subjects. J Hum Hypertens 2007; 21:564-70. [PMID: 17344908 DOI: 10.1038/sj.jhh.1002188] [Citation(s) in RCA: 33] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In patients with severe autonomic dysfunction, water ingestion elicits an acute pressor response. Hypertension may be associated with changes in cardiovascular autonomic modulation, but there is no information on the acute effects of water ingestion in patients with hypertension. In this study, we compared the effect of acute water ingestion on haemodynamic and autonomic responses of hypertensive and normotensive individuals. Eight patients with mild hypertension were compared to 10 normotensive individuals. After 30 min resting in the supine position all subjects ingested 500 ml of water. At baseline and after water ingestion, venous blood samples for plasma volume determination were collected, and electrocardiographic tracings, finger blood pressure, forearm blood flow and muscle sympathetic nerve activity (MSNA) were obtained. Water ingestion resulted in similar and minor reduction in plasma volume. Systolic and diastolic blood pressure increased in both hypertensive (mean+/-s.d.: 19/14+/-6/3 mm Hg) and normotensive subjects (17/14+/-6/3 mm Hg). There was an increase in forearm vascular resistance and in MSNA. Heart rate was reduced (hypertensive: 5+/-1 beats/min, normotensive: 5+/-6 beats/min) and the high-frequency component of heart rate and systolic blood pressure variability was increased. In hypertensive and normotensive individuals, acute water ingestion elicits a pressor response, an effect that is most likely determined by an increased vasoconstrictor sympathetic activity, and is counterbalanced by an increase in blood pressure and heart rate vagal modulation.
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Affiliation(s)
- C C Callegaro
- Cardiology Division, Hospital de Clínicas de Porto Alegre, Federal University of Rio Grande do Sul, Rua Ramiro Barcelos 2350, 90035-007 Porto Alegre, RS, Brazil
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13
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14
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Schrank IS, Mores MA, Costa JL, Frazzon AP, Soncini R, Schrank A, Vainstein MH, Silva SC. Influence of enrichment media and application of a PCR based method to detect Salmonella in poultry industry products and clinical samples. Vet Microbiol 2001; 82:45-53. [PMID: 11423194 DOI: 10.1016/s0378-1135(01)00350-9] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
To attempt the rapid detection of Salmonella enterica, we have coupled a culture procedure with PCR amplification of the genus-specific invE/invA genes. The method was applied to different kinds of samples from the poultry industry and evaluated by using hydrolyzed feather meal, meat meal, litter and viscera, all experimentally inoculated with a known number of Salmonella followed by cultivation in selenite--cystine broth prior to the PCR reaction. The expected 457bp specific DNA fragment could be amplified from dilutions containing as few as 5.7CFU, indicating that the PCR technique can be successfully coupled with culture in an enrichment broth to distinguish Salmonella species from other enteric bacteria present in samples from the poultry industry. Tetrathionate broth proved to be a much better enrichment media compared to selenite-cystine when the presence of Salmonella was evaluated by PCR in 1-day-old chicks experimentally infected with known numbers of Salmonella. Samples included cecal tonsils and viscera, collected at 48h and 7 days postinfection. The PCR technique was more sensitive in detecting infected animals than the standard microbiological procedure, which detected only 47% of all PCR positive samples.
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Affiliation(s)
- I S Schrank
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
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15
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Abstract
4'-Hydroxy-7,8-[2-(2-hydroxyisopropyl)dihydrofuran]flavan and 4',7-dihydroxy-8-(3,3-dimethylallyl)flavan, together with 10 known plant constituents, were obtained from the trunk bark of Brosimum acutifolium. Their structures were elucidated by spectroscopic methods, including 2D NMR spectroscopic techniques.
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Affiliation(s)
- S L Torres
- Laboratório de Química-Pesquisa, Universidade Federal do Pará, Belém, Brazil
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16
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Conceição MJ, Corrêa A, Teixeira A, Moura DC, Silva OC, Silva SC. Partial lack of susceptibility to Schistosoma mansoni infection of Biomphalaria glabrata strains from Itanhomi (Minas Gerais, Brazil) after fourteen years of laboratory maintenance. Mem Inst Oswaldo Cruz 1999; 94:425-6. [PMID: 10348995 DOI: 10.1590/s0074-02761999000300026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- M J Conceição
- Departamento de Medicina Preventiva, Hospital Universitário Clementino Fraga Filho, Rio de Janeiro, RJ, Brasil
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17
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Caldas ED, Coelho R, Souza LC, Silva SC. Organochlorine pesticides in water, sediment, and fish of Paranoá Lake of Brasilia, Brazil. Bull Environ Contam Toxicol 1999; 62:199-206. [PMID: 9933318 DOI: 10.1007/s001289900860] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Affiliation(s)
- E D Caldas
- University of Brasilia, Department of Pharmaceutical Sciences, 70919-970, Brasilia, DF, Brazil
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18
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Conceição MJ, Argento CA, Chagas VL, Takiya CM, Moura DC, Silva SC. Prognosis of schistosomiasis mansoni patients infected with hepatitis B virus. Mem Inst Oswaldo Cruz 1999; 93 Suppl 1:255-8. [PMID: 9921363 DOI: 10.1590/s0074-02761998000700047] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
A clinical study on the evolution of patients with schistosomiasis mansoni has been conducted since 1983 at the outpatient clinic of the Infectious and Parasitic Disease Service in the Clementino Fraga Filho University Hospital in Rio de Janeiro, Brazil, comparing prevalence of positive tests for HBsAg, anti-HBsAg, and anti-HBc among patients infected with Schistosoma mansoni coming from various regions of Brazil and with different clinical forms of the disease. A non-significant predominance of HBsAg, anti-HBsAg, and anti-HBc was detected among patients with the hepatosplenic form of schistosomiasis, who presented a more severe clinical evolution with a higher frequency of hematemesis and/or melena, in addition to the development of macronodular cirrhosis and a worse prognosis as compared to patients with the toxemic form, schistosomiasis-infection and the hepatointestinal form.
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Affiliation(s)
- M J Conceição
- Departamento de Medicina Preventiva, Hospital Universitário Clementino Fraga Filho, Rio de Janeiro, Brasil
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19
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de Oliveira EE, Silva SC, Soares AJ, Attux C, Cruvinel B, Silva MDR. [Killer toxin and enzyme production by Candida albicans isolated from buccal mucosa in patients with cancer]. Rev Soc Bras Med Trop 1998; 31:523-7. [PMID: 9859695] [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: 02/09/2023] Open
Abstract
Opportunistic infections of the oral cavity are primarily caused by Candida and frequently occur in patients with cancer who are undergoing chemotherapy and antibiotic treatment. Of the specimens received from the oral mucosa of 44 patients with cancer, 25 (56.8%) yielded Candida on culture in Sabouraud agar. Twenty four of these isolates were identified as C. albicans (96%) and 1 as C. krusei (4%). The phenotypic characteristics of these isolates showed that all of them were strongly proteolytic, had a high ability to produce phospholipase, and presented the byotypes characterized as 811 (95.8%) and 511 (4.2%) in terms of susceptibility to killer toxins.
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Affiliation(s)
- E E de Oliveira
- Departamento de Microbiologia, Imunologia, Parasitologia e Patologia, Universidade Federal de Goiás, Goiânia
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20
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Ferraz MB, Pinheiro GR, Helfenstein M, Albuquerque E, Rezende C, Roimicher L, Brandao L, Silva SC, Pinheiro GC, Atra E. Combination therapy with methotrexate and chloroquine in rheumatoid arthritis. A multicenter randomized placebo-controlled trial. Scand J Rheumatol 1994; 23:231-6. [PMID: 7973475 DOI: 10.3109/03009749409103721] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.5] [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: 01/28/2023]
Abstract
To compare the efficacy of the combination therapy Methotrexate (MTX) and Chloroquine (CHLO) with MTX and Placebo (PLA) in the treatment of Rheumatoid Arthritis. A total of 82 patients with Rheumatoid Arthritis (RA), diagnosed according to the American College of Rheumatology criteria, received orally either MTX 7.5 mg/week and CHLO 250 mg/day or MTX 7.5 mg/week and PLA 1 tablet/day. Adverse effects (AE) were monitored monthly and disease activity was assessed at 0, 2, 4 and 6 months. Sixty-eight patients completed the study. All outcome measures improved significantly in both treatment groups. Patients receiving MTX/CHLO ended the study with a significantly lower joint count, greater grip strength and better functional ability the patients in the MTX/PLA group, respectively; 4.5 vs 7.5 (P < 0.05), 113.3 vs 89.1 (P < 0.05) and 0.636 vs 0.811 (P < 0.05). Mild AE were more frequently observed in the MTX/CHLO, 17 events in 15 patients, compared to 9 events in 8 patients in the MTX/PLA group (NS). These data indicate that MTX/CHLO is slightly more efficacious and toxic than is MTX/PLA in the treatment of RA.
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Affiliation(s)
- M B Ferraz
- Escola Paulista de Medicina, Disciplina de Reumatologia, Sao Paulo, Brazil
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21
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Ito AS, Azzellini GC, Silva SC, Serra O, Szabo AG. Optical absorption and fluorescence spectroscopy studies of ground state melanin-cationic porphyrins complexes. Biophys Chem 1992; 45:79-89. [PMID: 1467446 DOI: 10.1016/0301-4622(92)87025-e] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Optical absorption and fluorescence spectroscopies were employed in the study of the interaction between synthetic L-dopa (dihydroxyphenylalanine) melanin and the cationic porphyrins tetrakis(4-N-methylpyridyl) porphyrin (TMPyP), tetrakis(4-N-benzylpyridyl)porphyrin (TBzPyP), zinc tetrakis(4-N-methylpyridyl)porphyrin (ZnTMPyP) and zinc tetrakis (4-N-benzylpyridyl)porphyrin (ZnTBzPyP). Optical absorption and fluorescence properties of the porphyrins were dependent on the symmetry of the central ring. No evidence was found for dimerization of the porphyrins in phosphate buffer, pH 7, in the concentration range between 4 x 10(-8) to 5 x 10(-5) M. Addition of L-dopa melanin red shifted the optical absorption spectra of porphyrins, concomitant to broadening and reduction in intensity of the bands. L-Dopa melanin also strongly quenched the fluorescence of the porphyrins. Time resolution of the fluorescence decay of porphyrins showed at least two lifetimes that were only slightly modified in the presence of melanin. The interaction between melanin and porphyrin resulted in the formation of non-fluorescent ground state complexes. It was found that there are two different classes of binding sites in melanin for complexation with cationic porphyrins and the values of dissociation constants are of the order of 10(-8) M. These values and the number of binding sites are dependent on the nature of the porphyrins. It was shown that the binding has electrostatic origin, but it is also affected by metal coordination and hydrophobic interaction.
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Affiliation(s)
- A S Ito
- Instituto de Física, Universidade de São Paulo, Brasil
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Silva SC. [Oxidizing action of Germekil, Zefirol and Deniges on endodontic instruments]. Rev Gaucha Odontol 1972; 20:292-6. [PMID: 4515453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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