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Roquini V, Mengarda AC, Cajas RA, Martins-da-Silva MF, Godoy-Silva J, Santos GA, Espírito-Santo MCC, Pavani TFA, Melo VA, Salvadori MC, Teixeira FS, Rando DGG, de Moraes J. The Existing Drug Nifuroxazide as an Antischistosomal Agent: In Vitro, In Vivo, and In Silico Studies of Macromolecular Targets. Microbiol Spectr 2023; 11:e0139323. [PMID: 37409934 PMCID: PMC10434008 DOI: 10.1128/spectrum.01393-23] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Accepted: 06/15/2023] [Indexed: 07/07/2023] Open
Abstract
Schistosomiasis is a parasitic disease that afflicts approximately 250 million people worldwide. There is an urgent demand for new antiparasitic agents because praziquantel, the only drug available for the treatment of schistosomiasis, is not universally effective and may derail current progress toward the WHO goal of eliminating this disease as a public health problem by 2030. Nifuroxazide (NFZ), an oral nitrofuran antibiotic, has recently been explored to be repurposed for parasitic diseases. Here, in vitro, in vivo, and in silico studies were conducted to evaluate the activity of NFZ on Schistosoma mansoni. The in vitro study showed significant antiparasitic activity, with 50% effective concentration (EC50) and 90% effective concentration (EC90) values of 8.2 to 10.8 and 13.7 to 19.3 μM, respectively. NFZ also affected worm pairing and egg production and induced severe damage to the tegument of schistosomes. In vivo, a single oral dose of NFZ (400 mg/kg of body weight) to mice harboring either prepatent or patent S. mansoni infection significantly reduced the total worm burden (~40%). In patent infection, NFZ achieved a high reduction in the number of eggs (~80%), but the drug caused a low reduction in the egg burden of animals with prepatent infection. Finally, results from in silico target fishing methods predicted that serine/threonine kinases could be one of the potential targets for NFZ in S. mansoni. Overall, the present study revealed that NFZ possesses antischistosomal properties, mainly in terms of egg burden reduction in animals with patent S. mansoni infection. IMPORTANCE The increasing recognition of the burden imposed by helminthiasis, associated with the limited therapeutic arsenal, has led to initiatives and strategies to research and develop new drugs for the treatment of schistosomiasis. One of these strategies is drug repurposing, which considers low-risk compounds with potentially reduced costs and shorter time for development. In this study, nifuroxazide (NFZ) was evaluated for its anti-Schistosoma mansoni potential through in vitro, in vivo, and in silico studies. In vitro, NFZ affected worm pairing and egg production and induced severe damage to the tegument of schistosomes. In vivo, a single oral dose of NFZ (400 mg/kg) to mice harboring either prepatent or patent S. mansoni infection significantly reduced the total worm burden and egg production. In silico investigations have identified serine/threonine kinases as a molecular target for NFZ. Collectively, these results implied that NFZ might be a potential therapeutic candidate for the treatment of schistosomiasis.
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Affiliation(s)
- Vinícius Roquini
- Research Center on Neglected Diseases, Guarulhos University, Guarulhos, São Paulo, Brazil
| | - Ana C. Mengarda
- Research Center on Neglected Diseases, Guarulhos University, Guarulhos, São Paulo, Brazil
| | - Rayssa A. Cajas
- Research Center on Neglected Diseases, Guarulhos University, Guarulhos, São Paulo, Brazil
| | | | - Julia Godoy-Silva
- Research Center on Neglected Diseases, Guarulhos University, Guarulhos, São Paulo, Brazil
| | - Gustavo A. Santos
- Research Center on Neglected Diseases, Guarulhos University, Guarulhos, São Paulo, Brazil
| | - Maria Cristina C. Espírito-Santo
- Laboratory of Immunopathology of Schistosomiasis (LIM-06), Department of Infectious and Parasitic Diseases, Faculty of Medicine, University of São Paulo, São Paulo, São Paulo, Brazil
- Laboratory of Helminthology, Institute of Tropical Medicine, University of São Paulo, São Paulo, São Paulo, Brazil
| | - Thais F. A. Pavani
- Biological Chemistry Post-Graduate Course, Institute of Environmental, Chemical and Pharmaceutical Sciences, Federal University of São Paulo, Diadema, São Paulo, Brazil
| | - Vanusa A. Melo
- Biological Chemistry Post-Graduate Course, Institute of Environmental, Chemical and Pharmaceutical Sciences, Federal University of São Paulo, Diadema, São Paulo, Brazil
| | - Maria C. Salvadori
- Institute of Physics, University of São Paulo, São Paulo, São Paulo, Brazil
| | | | - Daniela G. G. Rando
- Chemico-Pharmaceutical Research Group, Institute of Environmental, Chemical and Pharmaceutical Sciences, Federal University of São Paulo, Diadema, São Paulo, Brazil
| | - Josué de Moraes
- Research Center on Neglected Diseases, Guarulhos University, Guarulhos, São Paulo, Brazil
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Porto R, Mengarda AC, Cajas RA, Salvadori MC, Teixeira FS, Arcanjo DDR, Siyadatpanah A, Pereira MDL, Wilairatana P, de Moraes J. Antiparasitic Properties of Cardiovascular Agents against Human Intravascular Parasite Schistosoma mansoni. Pharmaceuticals (Basel) 2021; 14:ph14070686. [PMID: 34358112 PMCID: PMC8308662 DOI: 10.3390/ph14070686] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [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: 06/18/2021] [Revised: 07/12/2021] [Accepted: 07/13/2021] [Indexed: 01/21/2023] Open
Abstract
The intravascular parasitic worm Schistosoma mansoni is a causative agent of schistosomiasis, a disease of great global public health significance. Praziquantel is the only drug available to treat schistosomiasis and there is an urgent demand for new anthelmintic agents. Adopting a phenotypic drug screening strategy, here, we evaluated the antiparasitic properties of 46 commercially available cardiovascular drugs against S. mansoni. From these screenings, we found that amiodarone, telmisartan, propafenone, methyldopa, and doxazosin affected the viability of schistosomes in vitro, with effective concentrations of 50% (EC50) and 90% (EC90) values ranging from 8 to 50 µM. These results were further supported by scanning electron microscopy analysis. Subsequently, the most effective drug (amiodarone) was further tested in a murine model of schistosomiasis for both early and chronic S. mansoni infections using a single oral dose of 400 mg/kg or 100 mg/kg daily for five consecutive days. Amiodarone had a low efficacy in chronic infection, with the worm and egg burden reduction ranging from 10 to 30%. In contrast, amiodarone caused a significant reduction in worm and egg burden in early infection (>50%). Comparatively, treatment with amiodarone is more effective in early infection than praziquantel, demonstrating the potential role of this cardiovascular drug as an antischistosomal agent.
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Affiliation(s)
- Raquel Porto
- Research Center for Neglected Diseases, Guarulhos University, Praça Tereza Cristina 229, São Paulo 07023-070, SP, Brazil; (R.P.); (A.C.M.); (R.A.C.)
| | - Ana C. Mengarda
- Research Center for Neglected Diseases, Guarulhos University, Praça Tereza Cristina 229, São Paulo 07023-070, SP, Brazil; (R.P.); (A.C.M.); (R.A.C.)
| | - Rayssa A. Cajas
- Research Center for Neglected Diseases, Guarulhos University, Praça Tereza Cristina 229, São Paulo 07023-070, SP, Brazil; (R.P.); (A.C.M.); (R.A.C.)
| | - Maria C. Salvadori
- Institute of Physics, University of São Paulo, São Paulo 05508-060, SP, Brazil; (M.C.S.); (F.S.T.)
| | - Fernanda S. Teixeira
- Institute of Physics, University of São Paulo, São Paulo 05508-060, SP, Brazil; (M.C.S.); (F.S.T.)
| | - Daniel D. R. Arcanjo
- Department of Biophysics and Physiology, Federal University of Piaui, Teresina 64049-550, PI, Brazil;
| | - Abolghasem Siyadatpanah
- Ferdows School of Paramedical and Health, Birjand University of Medical Sciences, Birjand 9717853577, Iran;
| | - Maria de Lourdes Pereira
- CICECO-Aveiro Institute of Materials & Department of Medical Sciences, University of Aveiro, 3810-193 Aveiro, Portugal;
| | - Polrat Wilairatana
- Department of Clinical Tropical Medicine, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand
- Correspondence: (P.W.); (J.d.M.)
| | - Josué de Moraes
- Research Center for Neglected Diseases, Guarulhos University, Praça Tereza Cristina 229, São Paulo 07023-070, SP, Brazil; (R.P.); (A.C.M.); (R.A.C.)
- Correspondence: (P.W.); (J.d.M.)
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Silva MP, Silva TM, Mengarda AC, Salvadori MC, Teixeira FS, Alencar SM, Luz Filho GC, Bueno-Silva B, de Moraes J. Brazilian red propolis exhibits antiparasitic properties in vitro and reduces worm burden and egg production in an mouse model harboring either early or chronic Schistosoma mansoni infection. J Ethnopharmacol 2021; 264:113387. [PMID: 32918996 DOI: 10.1016/j.jep.2020.113387] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [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: 07/25/2020] [Revised: 08/25/2020] [Accepted: 09/04/2020] [Indexed: 06/11/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Propolis has been used in folk medicine for thousands of years and, in the past few decades, it has attracted renewed interest. Although propolis has been traditionally used in many communities worldwide against parasitic diseases, its effect against Schistosoma mansoni infection remains unclear. AIM OF THE STUDY To demonstrate the effects of Brazilian red propolis on Schistosoma mansoni ex vivo and in an animal model of schistosomiasis. MATERIALS AND METHODS In vitro, we monitored phenotypic and tegumental changes as well as the effects of the crude extract of propolis on pairing and egg production. In a mouse infected with either immature (early infection) or adult (chronic infection) worms, propolis was administered by oral gavage and we studied the influence of this natural product on worm burden and egg production. RESULTS Propolis 25 μg/mL reduced motility and caused 100% mortality of adult parasites ex vivo. Further analysis revealed a pronounced reduction in oviposition after exposure to propolis at sub-lethal concentrations. In addition, scanning electron microscopy showed morphological alterations in the tegument of schistosomes. In the animal model, propolis markedly reduced worm burden and egg production in both early and chronic S. mansoni infection when compared to untreated control animals. CONCLUSIONS The efficacy of Brazilian red propolis in both in vitro and in vivo studies suggests its potential anthelmintic properties against S. mansoni infection.
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Affiliation(s)
- Marcos P Silva
- Núcleo de Pesquisa Em Doenças Negligenciadas, Universidade Guarulhos, Guarulhos, SP, Brazil.
| | - Thiago M Silva
- Núcleo de Pesquisa Em Doenças Negligenciadas, Universidade Guarulhos, Guarulhos, SP, Brazil.
| | - Ana C Mengarda
- Núcleo de Pesquisa Em Doenças Negligenciadas, Universidade Guarulhos, Guarulhos, SP, Brazil.
| | - Maria C Salvadori
- Instituto de Física, Universidade de São Paulo, São Paulo, SP, Brazil.
| | | | - Severino M Alencar
- Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, São Paulo, SP, Brazil.
| | | | - Bruno Bueno-Silva
- Departamento de Odontologia, Universidade Guarulhos, Guarulhos, SP, Brazil.
| | - Josué de Moraes
- Núcleo de Pesquisa Em Doenças Negligenciadas, Universidade Guarulhos, Guarulhos, SP, Brazil.
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Xavier RP, Mengarda AC, Silva MP, Roquini DB, Salvadori MC, Teixeira FS, Pinto PL, Morais TR, Ferreira LLG, Andricopulo AD, de Moraes J. H1-antihistamines as antischistosomal drugs: in vitro and in vivo studies. Parasit Vectors 2020; 13:278. [PMID: 32487175 PMCID: PMC7268501 DOI: 10.1186/s13071-020-04140-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [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: 02/22/2020] [Accepted: 05/21/2020] [Indexed: 12/18/2022] Open
Abstract
Background Schistosomiasis is a socioeconomically devastating parasitic infection afflicting hundreds of millions of people and animals worldwide. It is the most important helminth infection, and its treatment relies solely on the drug praziquantel. Oral H1-antihistamines are available worldwide, and these agents are among the most widely used of all medications in children and adults. Given the importance of the drug repositioning strategy, we evaluated the antischistosomal properties of the H1-antihistamine drugs commonly used in clinical practices. Methods Twenty-one antihistamine drugs were initially screened against adult schistosomes ex vivo. Subsequently, we investigated the anthelmintic properties of these antihistamines in a murine model of schistosomiasis for both early and chronic S. mansoni infections at oral dosages of 400 mg/kg single dose or 100 mg/kg daily for five consecutive days. We also demonstrated and described the ability of three antihistamines to induce tegumental damage in schistosomes through the use of scanning electron microscopy. Results From phenotypic screening, we found that desloratadine, rupatadine, promethazine, and cinnarizine kill adult S. mansoni in vitro at low concentrations (5–15 µM). These results were further supported by scanning electron microscopy analysis. In an animal model, rupatadine and cinnarizine revealed moderate worm burden reductions in mice harboring either early or chronic S. mansoni infection. Egg production, a key mechanism for both transmission and pathogenesis, was also markedly inhibited by rupatadine and cinnarizine, and a significant reduction in hepatomegaly and splenomegaly was recorded. Although less effective, desloratadine also revealed significant activity against the adult and juvenile parasites. Conclusions Although the worm burden reductions achieved are all only moderate, comparatively, treatment with any of the three antihistamines is more effective in early infection than praziquantel. On the other hand, the clinical use of H1-antihistamines for the treatment of schistosomiasis is highly unlikely.![]()
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Affiliation(s)
- Rogério P Xavier
- Núcleo de Pesquisa em Doenças Negligenciadas, Universidade Guarulhos, Guarulhos, SP, Brazil
| | - Ana C Mengarda
- Núcleo de Pesquisa em Doenças Negligenciadas, Universidade Guarulhos, Guarulhos, SP, Brazil
| | - Marcos P Silva
- Núcleo de Pesquisa em Doenças Negligenciadas, Universidade Guarulhos, Guarulhos, SP, Brazil
| | - Daniel B Roquini
- Núcleo de Pesquisa em Doenças Negligenciadas, Universidade Guarulhos, Guarulhos, SP, Brazil
| | - Maria C Salvadori
- Instituto de Física, Universidade de São Paulo, São Paulo, SP, Brazil
| | | | - Pedro L Pinto
- Núcleo de Enteroparasitas, Instituto Adolfo Lutz, São Paulo, SP, Brazil
| | - Thiago R Morais
- Núcleo de Pesquisa em Doenças Negligenciadas, Universidade Guarulhos, Guarulhos, SP, Brazil
| | - Leonardo L G Ferreira
- Laboratório de Química Medicinal e Computacional, Instituto de Física de São Carlos, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Adriano D Andricopulo
- Laboratório de Química Medicinal e Computacional, Instituto de Física de São Carlos, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Josué de Moraes
- Núcleo de Pesquisa em Doenças Negligenciadas, Universidade Guarulhos, Guarulhos, SP, Brazil.
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Mengarda AC, Mendonça PS, Morais CS, Cogo RM, Mazloum SF, Salvadori MC, Teixeira FS, Morais TR, Antar GM, Lago JHG, Moraes J. Antiparasitic activity of piplartine (piperlongumine) in a mouse model of schistosomiasis. Acta Trop 2020; 205:105350. [PMID: 31962096 DOI: 10.1016/j.actatropica.2020.105350] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 12/30/2019] [Accepted: 01/17/2020] [Indexed: 01/09/2023]
Abstract
Schistosomiasis is one of the most important parasitic infections in terms of its negative effects on public health and economics. Since praziquantel is currently the only drug available to treat schistosomiasis, there is an urgent need to identify new anthelmintic agents. Piplartine, also known as piperlongumine, is a biologically active alkaloid/amide from peppers that can be detected in high amounts in the roots of Piper tuberculatum. Previously, it has been shown to have in vitro schistosomicidal effects. However, its anthelmintic activity in an animal host has not been reported. In the present work, in vivo antischistosomal properties of isolated piplartine were evaluated in a mouse model of schistosomiasis infected with either adult (patent infection) or juvenile (pre-patent infection) stages of Schistosoma mansoni. A single dose of piplartine (100, 200 or 400 mg/kg) or daily doses for five consecutive days (100 mg/kg/day) administered orally to mice infected with schistosomes resulted in a reduction in worm burden and egg production. Treatment with the highest piplartine dose (400 mg/kg) caused a significant reduction in a total worm burden of 60.4% (P < 0.001) in mice harbouring adult parasites. S. mansoni egg production, a process responsible for pathology in schistosomiasis, was also significantly inhibited by piplartine. Studies using scanning electron microscopy revealed substantial tegumental alterations in parasites recovered from mice. Since piplartine has well-characterized mechanisms of toxicity, is easily available, and is cost-effective, our results indicate that this bioactive molecule derived from medicinal plants could be a potential lead compound for novel antischistosomal agents.
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Affiliation(s)
- Ana C Mengarda
- Núcleo de Pesquisa em Doenças Negligenciadas, Universidade Guarulhos, Praça Tereza Cristina, 229, Centro, 07023-070, Guarulhos, SP, Brazil
| | - Poliana S Mendonça
- Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Santo André, São Paulo, 09210-180, Brazil
| | - Cristiane S Morais
- Núcleo de Pesquisa em Doenças Negligenciadas, Universidade Guarulhos, Praça Tereza Cristina, 229, Centro, 07023-070, Guarulhos, SP, Brazil
| | - Ramon M Cogo
- Núcleo de Pesquisa em Doenças Negligenciadas, Universidade Guarulhos, Praça Tereza Cristina, 229, Centro, 07023-070, Guarulhos, SP, Brazil
| | - Susana F Mazloum
- Núcleo de Pesquisa em Doenças Negligenciadas, Universidade Guarulhos, Praça Tereza Cristina, 229, Centro, 07023-070, Guarulhos, SP, Brazil
| | - Maria C Salvadori
- Instituto de Física, Universidade de São Paulo, São Paulo, SP, Brazil
| | | | - Thiago R Morais
- Núcleo de Pesquisa em Doenças Negligenciadas, Universidade Guarulhos, Praça Tereza Cristina, 229, Centro, 07023-070, Guarulhos, SP, Brazil
| | - Guilherme M Antar
- Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo, 05508-090, São Paulo, Brazil
| | - João Henrique G Lago
- Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Santo André, São Paulo, 09210-180, Brazil
| | - Josué Moraes
- Núcleo de Pesquisa em Doenças Negligenciadas, Universidade Guarulhos, Praça Tereza Cristina, 229, Centro, 07023-070, Guarulhos, SP, Brazil.
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Pereira VRD, Junior IJA, da Silveira LS, Geraldo RB, de F Pinto P, Teixeira FS, Salvadori MC, Silva MP, Alves LA, Capriles PVSZ, das C Almeida A, Coimbra ES, Pinto PLS, Couri MRC, de Moraes J, Da Silva Filho AA. In Vitro and in Vivo Antischistosomal Activities of Chalcones. Chem Biodivers 2018; 15:e1800398. [PMID: 30276965 DOI: 10.1002/cbdv.201800398] [Citation(s) in RCA: 5] [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: 08/09/2018] [Accepted: 10/01/2018] [Indexed: 01/18/2023]
Abstract
In this study, we evaluated the in vitro and in vivo schistosomicidal activities of chalcones against Schistosoma mansoni worms. In vitro assays revealed that chalcones 1 and 3 were the most active compounds, without affecting significantly mammalian cells. Confocal laser scanning microscopy and scanning electron microscopy studies revealed reduction on the numbers of tubercles and morphological alterations in the tegument of S. mansoni worms after in vitro incubation with chalcones 1 and 3. In a mouse model of schistosomiasis, the oral treatment (400 mg/kg) with chalcone 1 or 3 significantly caused a total worm burden reduction in mice. Chalcone 1 showed significant inhibition of the S. mansoni ATP diphosphohydrolase activity, which was corroborated by molecular docking studies. The results suggested that chalcones could be explored as lead compounds with antischistosomal properties.
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Affiliation(s)
- Vinícius R D Pereira
- Faculdade de Farmácia, Departamento de Ciências Farmacêuticas, Universidade Federal de Juiz de Fora, R. José Lourenço Kelmer s/n, Campus Universitário, 36036-900, Juiz de Fora, MG, Brazil
| | - Ismael J Alves Junior
- Faculdade de Farmácia, Departamento de Ciências Farmacêuticas, Universidade Federal de Juiz de Fora, R. José Lourenço Kelmer s/n, Campus Universitário, 36036-900, Juiz de Fora, MG, Brazil
| | - Lígia S da Silveira
- Departamento de Química, Universidade Federal de Juiz de Fora, Juiz de Fora, MG, Brazil
| | - Reinaldo B Geraldo
- Faculdade de Farmácia, Departamento de Ciências Farmacêuticas, Universidade Federal de Juiz de Fora, R. José Lourenço Kelmer s/n, Campus Universitário, 36036-900, Juiz de Fora, MG, Brazil
| | - Priscila de F Pinto
- Departamento de Bioquímica, Instituto de Ciências Biológicas, Universidade Federal de Juiz de Fora, Juiz de Fora, MG, Brazil
| | | | - Maria C Salvadori
- Instituto de Física, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Marcos P Silva
- Núcleo de Pesquisa em Doenças Negligenciadas, Universidade Guarulhos, Guarulhos, SP, Brazil
| | - Lara A Alves
- Programa de Pós-graduação em Modelagem Computacional, Departamento de Ciência da Computação, ICE, Universidade Federal de Juiz de Fora, Juiz de Fora, MG, Brazil
| | - Priscila V S Z Capriles
- Programa de Pós-graduação em Modelagem Computacional, Departamento de Ciência da Computação, ICE, Universidade Federal de Juiz de Fora, Juiz de Fora, MG, Brazil
| | - Ayla das C Almeida
- Departamento de Parasitologia, Microbiologia e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Juiz de Fora, Juiz de Fora, MG, Brazil
| | - Elaine S Coimbra
- Departamento de Parasitologia, Microbiologia e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Juiz de Fora, Juiz de Fora, MG, Brazil
| | - Pedro L S Pinto
- Núcleo de Enteroparasitas, Instituto Adolfo Lutz, São Paulo, SP, Brazil
| | - Mara R C Couri
- Departamento de Química, Universidade Federal de Juiz de Fora, Juiz de Fora, MG, Brazil
| | - Josué de Moraes
- Núcleo de Pesquisa em Doenças Negligenciadas, Universidade Guarulhos, Guarulhos, SP, Brazil
| | - Ademar A Da Silva Filho
- Faculdade de Farmácia, Departamento de Ciências Farmacêuticas, Universidade Federal de Juiz de Fora, R. José Lourenço Kelmer s/n, Campus Universitário, 36036-900, Juiz de Fora, MG, Brazil
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Silva MP, de Oliveira RN, Mengarda AC, Roquini DB, Allegretti SM, Salvadori MC, Teixeira FS, de Sousa DP, Pinto PL, da Silva Filho AA, de Moraes J. Antiparasitic activity of nerolidol in a mouse model of schistosomiasis. Int J Antimicrob Agents 2017; 50:467-472. [DOI: 10.1016/j.ijantimicag.2017.06.005] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Revised: 06/16/2017] [Accepted: 06/17/2017] [Indexed: 01/08/2023]
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Sgura R, dos Reis MC, Salvadori MC, Hernandes AC, Cesar PF, Medeiros IS. CO2 Laser Glazing Treatment of a Veneering Porcelain: Effects on Porosity, Translucency, and Mechanical Properties. Oper Dent 2014; 40:247-54. [PMID: 25268041 DOI: 10.2341/14-079-l] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This work tested CO2 laser as a glazing agent and investigated the effects of irradiation on the porosity, translucency, and mechanical properties of veneering porcelain. Sixty discs (diameter 3.5 × 2.0 mm) of veneering porcelain for Y-TZP frameworks (VM9, VITA Zahnfabrik) were sintered and had one of their faces mirror polished. The specimens were divided into six groups (n=10/group) according to surface treatment, as follows: no treatment-control; auto-glaze in furnace following manufacturer's instructions (G); and CO2 laser (45 or 50 W/cm(2)) applied for four or five minutes (L45/4, L45/5, L50/4, L50/5). Optical microscopy (Shimadzu, 100×) was conducted and the images were analyzed with Image J software for the determination of the following porosity parameters: area fraction, average size, and Feret diameter. The translucency parameter studied was masking ability, determined by color difference (ΔE) over black and white backgrounds (CM3370d, Konica Minolta). Microhardness and fracture toughness (indentation fracture) were measured with a Vickers indenter (HMV, Shimadzu). Contact atomic force microscopy (AFM) (50 × 50 μm(2), Nanoscope IIIA, Veeco) was performed at the center of one sample from each group, except in the case of L45/5. With regard to porosity and translucency parameters, auto-glazed and laser-irradiated specimens presented statistical similarity. The area fraction of the surface pores ranged between 2.4% and 5.4% for irradiated specimens. Group L50/5 presented higher microhardness when compared to the G group. The higher (1.1) and lower (0.8) values for fracture toughness (MPa.m(1/2)) were found in laser-irradiated groups (L50/4 and L45/4, respectively). AFM performed after laser treatment revealed changes in porcelain surface profile at a submicrometric scale, with the presence of elongated peaks and deep valleys.
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Salvadori MC, Teixeira FS, Sgubin LG, Araujo WWR, Spirin RE, Cattani M, Oks EM, Brown IG. Gold ion implantation into alumina using an "inverted ion source" configuration. Rev Sci Instrum 2014; 85:02B502. [PMID: 24593599 DOI: 10.1063/1.4824755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We describe an approach to ion implantation in which the plasma and its electronics are held at ground potential and the ion beam is injected into a space held at high negative potential, allowing considerable savings both economically and technologically. We used an "inverted ion implanter" of this kind to carry out implantation of gold into alumina, with Au ion energy 40 keV and dose (3-9) × 10(16) cm(-2). Resistivity was measured in situ as a function of dose and compared with predictions of a model based on percolation theory, in which electron transport in the composite is explained by conduction through a random resistor network formed by Au nanoparticles. Excellent agreement is found between the experimental results and the theory.
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Affiliation(s)
- M C Salvadori
- Institute of Physics, University of São Paulo, C.P. 66318, CEP 05315-970, São Paulo, S.P., Brazil
| | - F S Teixeira
- Institute of Physics, University of São Paulo, C.P. 66318, CEP 05315-970, São Paulo, S.P., Brazil
| | - L G Sgubin
- Institute of Physics, University of São Paulo, C.P. 66318, CEP 05315-970, São Paulo, S.P., Brazil
| | - W W R Araujo
- Institute of Physics, University of São Paulo, C.P. 66318, CEP 05315-970, São Paulo, S.P., Brazil
| | - R E Spirin
- Institute of Physics, University of São Paulo, C.P. 66318, CEP 05315-970, São Paulo, S.P., Brazil
| | - M Cattani
- Institute of Physics, University of São Paulo, C.P. 66318, CEP 05315-970, São Paulo, S.P., Brazil
| | - E M Oks
- High Current Electronics Institute, Russian Academy of Sciences, Tomsk 634055, Russia and National Research Tomsk Polytechnic University, Tomsk 634050, Russia
| | - I G Brown
- Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
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Salvadori MC, Teixeira FS, Sgubin LG, Araujo WWR, Spirin RE, Oks EM, Brown IG. Performance of an inverted ion source. Rev Sci Instrum 2013; 84:023506. [PMID: 23464210 DOI: 10.1063/1.4793377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Whereas energetic ion beams are conventionally produced by extracting ions (say, positive ions) from a plasma that is held at high (positive) potential, with ion energy determined by the potential drop through which the ions fall in the beam formation electrode system, in the device described here the plasma and its electronics are held at ground potential and the ion beam is formed and injected energetically into a space maintained at high (negative) potential. We refer to this configuration as an "inverted ion source." This approach allows considerable savings both technologically and economically, rendering feasible some ion beam applications, in particular small-scale ion implantation, that might otherwise not be possible for many researchers and laboratories. We have developed a device of this kind utilizing a metal vapor vacuum arc plasma source, and explored its operation and beam characteristics over a range of parameter variation. The downstream beam current has been measured as a function of extraction voltage (5-35 kV), arc current (50-230 A), metal ion species (Ti, Nb, Au), and extractor grid spacing and beamlet aperture size (3, 4, and 5 mm). The downstream ion beam current as measured by a magnetically-suppressed Faraday cup was up to as high as 600 mA, and with parametric variation quite similar to that found for the more conventional metal vapor vacuum arc ion source.
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Affiliation(s)
- M C Salvadori
- Institute of Physics, University of São Paulo, C.P. 66318, CEP 05315-970, São Paulo S.P., Brazil.
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Ferreira J, Teixeira FS, Zanatta AR, Salvadori MC, Gordon R, Oliveira ON. Tailored SERS substrates obtained with cathodic arc plasma ion implantation of gold nanoparticles into a polymer matrix. Phys Chem Chem Phys 2012; 14:2050-5. [DOI: 10.1039/c2cp23287a] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Salvadori MC, Teixeira FS, Araújo WWR, Sgubin LG, Sochugov NS, Spirin RE, Brown IG. A high voltage pulse power supply for metal plasma immersion ion implantation and deposition. Rev Sci Instrum 2010; 81:124703. [PMID: 21198040 DOI: 10.1063/1.3518969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We describe the design and implementation of a high voltage pulse power supply (pulser) that supports the operation of a repetitively pulsed filtered vacuum arc plasma deposition facility in plasma immersion ion implantation and deposition (Mepiiid) mode. Negative pulses (micropulses) of up to 20 kV in magnitude and 20 A peak current are provided in gated pulse packets (macropulses) over a broad range of possible pulse width and duty cycle. Application of the system consisting of filtered vacuum arc and high voltage pulser is demonstrated by forming diamond-like carbon (DLC) thin films with and without substrate bias provided by the pulser. Significantly enhanced film∕substrate adhesion is observed when the pulser is used to induce interface mixing between the DLC film and the underlying Si substrate.
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Affiliation(s)
- M C Salvadori
- Institute of Physics, University of São Paulo, C.P. 66318, CEP 05315-970 São Paulo SP, Brazil.
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Wiederkehr RS, Salvadori MC, Degasperi FT, Cattani M. Development of microvalves for gas flow control in micronozzles using PVDF piezoelectric polymer. ACTA ACUST UNITED AC 2008. [DOI: 10.1088/1742-6596/100/5/052046] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Abstract
We describe a small hollow-cathode plasma source suitable for small-scale materials synthesis and modification application. The supporting electrical system is minimal. The gaseous plasma source delivers a plasma ion current of up to about 1 mA. Here we outline the source construction and operation, and present some of its basic performance characteristics.
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Affiliation(s)
- A Vizir
- High Current Electronics Institute, Russian Academy of Sciences, Tomsk 634055, Russia
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Teixeira FS, Mansano RD, Salvadori MC, Cattani M, Brown IG. Atomic force microscope nanolithography of polymethylmethacrylate polymer. Rev Sci Instrum 2007; 78:053702. [PMID: 17552820 DOI: 10.1063/1.2736311] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
We describe a nanolithography process for a polymethylmethacrylate (PMMA) surface using scanning contact atomic force microscopy. Parallel furrows were scribed with a pyramidal silicon tip using the same scan mechanism as used to image samples. The PMMA was first electron beam irradiated using a scanning electron microscope and developed. The topography formed is reproducible and predictable. Material from the region where the tip scribes is moved to nearby regions, and aligned, elongated PMMA fragments are seen to decorate the valleys between furrows.
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Affiliation(s)
- F S Teixeira
- Laboratory of Integrated Systems, Polytechnic School, University of São Paulo, Avenida Professor Luciano Gualberto, Travessa R-158, CEP 05508-900 São Paulo, Brazil
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Suarez-Kurtz G, Ribeiro FM, Salvadori MC, Struchiner CJ. Carbamazepine: a bioequivalence study and limited sampling modeling. Int J Clin Pharmacol Ther 2002; 40:424-30. [PMID: 12358160 DOI: 10.5414/cpp40424] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [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: 11/18/2022] Open
Abstract
OBJECTIVES To assess the bioequivalence of 2 formulations of carbamazepine and to develop and validate limited sampling strategy (LSS) models for estimating the area under the plasma concentration-time curve (AUC0-infinity) and the peak plasma concentration (Cmax) of carbamazepine. METHODS Twenty-four (12 men, 12 women) healthy volunteers received single oral doses (400 mg) of carbamazepine, as reference and test conventional-release formulations, in a standard 2-sequence, 2-period crossover design. Bioequivalence assessment was based on the individual ratios of log-transformed values of AUC0-infinity and Cmax LSS modeling was developed in a training set of 12 randomly assigned volunteers and was validated on the other 12 subjects (validation set). RESULTS Carbamazepine AUC0-infinity and Cmax can be accurately predicted (R2 = 0.89 - 0.95, precision = 2.6 - 7.2%) by single-point (72 h) and 2-point LSS models (6, 32 h), respectively. Bioequivalence assessments based on LSS-derived AUC0-infinity and Cmax provided results similar to those obtained using all the concentration-in-plasma data points, and indicated that the 2 formulations are bioequivalent. CONCLUSION One-and 2-point LSS models provided accurate estimates of carbamazepine's AUC0-infinity and Cmax, and allowed correct assessment of bioequivalence between the formulations studied.
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Affiliation(s)
- G Suarez-Kurtz
- Coordenação de Pesquisa, Instituto Nacional de Câncer, Rio de Janeiro, Brazil.
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Queiroz-Neto A, Zamur G, Carregaro AB, Mataqueiro MI, Salvadori MC, Azevedo CP, Harkins JD, Tobin T. Effects of caffeine on locomotor activity of horses: determination of the no-effect threshold. J Appl Toxicol 2001; 21:229-34. [PMID: 11404835 DOI: 10.1002/jat.748] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Caffeine is the legal stimulant consumed most extensively by the human world population and may be found eventually in the urine and/or blood of race horses. The fact that caffeine is in foods led us to determine the highest no-effect dose (HNED) of caffeine on the spontaneous locomotor activity of horses and then to quantify this substance in urine until it disappeared. We built two behavioural stalls equipped with juxtaposed photoelectric sensors that emit infrared beams that divide the stall into nine sectors in a 'tic-tac-toe' fashion. Each time a beam was interrupted by a leg of the horse, a pulse was generated; the pulses were counted at 5-min intervals and stored by a microcomputer. Environmental effects were minimized by installing exhaust fans producing white noise that obscured outside sounds. One-way observation windows prevented the animals from seeing outside. The sensors were turned on 45 min before drug administration (saline control or caffeine). The animals were observed for up to 8 h after i.v. administration of 2.0, 2.5, 3.0 or 5.0 mg caffeine kg(-1). The HNED of caffeine for stimulation of the spontaneous locomotor activity of horses was 2.0 mg kg(-1). The quantification of caffeine in urine and plasma samples was done by gradient HPLC with UV detection. The no-effect threshold should not be greater than 2.0 microg caffeine ml(-1) plasma or 5.0 microg caffeine ml(-1) urine.
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Affiliation(s)
- A Queiroz-Neto
- Departamento de Morfologia e Fisiologia Animal, Faculdade de Ciências Agrárias e Veterinárias, Câmpus de Jaboticabal, FCAV/UNESP, 14884-900 Jaboticabal, SP, Brazil.
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Abstract
As hydrocortisone is an endogenous substance, it is first necessary to establish its normal concentrations so as to be able to control its use in racing animals. This study was designed to establish the hydrocortisone concentrations in post-race urine samples of horses racing in Brazil and also to evaluate the results in relation to the international threshold set for this drug. Urine samples were analysed by HPLC-UV. The results were evaluated according to the concentration range as well as sex and time of sample collection (afternoon or evening races). The results showed a high degree of variation in the concentrations of hydrocortisone in the urine (93 +/- 69 ng/ml). The maximum concentration observed was 646 ng/ml, although only a few horses (around 1%) showed levels within the range 500-650 ng/ml, 91% being in the range 0-150 ng/ml. The data suggested a normal distribution curve. Statistical analysis showed no significant influence of sex or time of sample collection.
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Affiliation(s)
- L M Ribeiro Neto
- Department of Antidoping Control, Jockey Club of São Paulo, SP, Brazil
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Abstract
Due to the widespread use of dexamethasone in racing horses, mostly in low doses by intra-articular administration for the treatment of inflammatory processes, a method is developed to detect this drug in horse urine samples using liquid-liquid extraction followed by immunoaffinity chromatography. Liquid chromatography with diode-array detection is used for the identification of the drug. The use of immunoaffinity columns enhances the selectivity of the analysis, and the results show that dexamethasone can be detected up to 28 h after intra-articular administration.
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Affiliation(s)
- L M Ribeiro Neto
- Departamento de Controle e Pesquisas Antidopagem, Jockey Club de São Paulo, SP, Brazil
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Ribeiro Neto LM, Spinosa HS, Salvadori MC. The use of ELISA tests and immunoaffinity chromatography combined with reversed-phase high-performance liquid chromatography for dexamethasone detection in equine urine. J Anal Toxicol 1997; 21:393-6. [PMID: 9288594 DOI: 10.1093/jat/21.5.393] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Dexamethasone is a corticosteroid drug widely used in racehorses because of its anti-inflammatory effect. It is, therefore, frequently detected in antidoping tests. A method for the antidoping control of dexamethasone in equine urine using screening by ELISA and confirmation by immunoaffinity chromatography combined with reversed-phase high-performance liquid chromatography-diode array detection (HPLC-DAD) is described. The ELISA test is frequently used in antidoping tests for its sensitivity, relative speed, and low cost. The test showed linearity in the range of 4-500 ng/mL of urine, and the intra-assay and interassay imprecision were 9.4 and 9.7%, respectively. The confirmation method showed a limit of detection of 4 ng/mL for dexamethasone. The intra-assay and interassay imprecisions were 10.3 and 14.4%, respectively. The HPLC-DAD showed a limit of detection of 5 ng and linearity in the range of 25-500 ng of dexamethasone. The absolute method recovery was 56.4%. The proposed method detected dexamethasone up to 52 h after administration and proved to be adequate for the antidoping control.
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Affiliation(s)
- L M Ribeiro Neto
- Departamento de Controle e Pesquisas Antidopagem, Jockey Club de São Paulo Rua Bento Frias, Brazil
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Abstract
To determine the actual amount of diethylstilbestrol, hexestrol, and dienestrol in formulations such as pellets and oily injections that are illegally available on the Brazilian market, a simple methanol extraction is used for the analysis of the pellets and an ether extraction with Sephadex columns (for clean-up) is used for the oily injections. High-performance thin-layer chromatography is used for identification (as a qualitative and semiquantitative method), and high-performance liquid chromatography is used for quantitation. The results of the analysis show that all the formulations are not in accordance with the information listed on their labels.
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Affiliation(s)
- E S Nascimento
- Departmento de Análises Clínicas e Toxicology, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo
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Neto LM, Andraus MH, Salvadori MC. Determination of phenylbutazone and oxyphenbutazone in plasma and urine samples of horses by high-performance liquid chromatography and gas chromatography-mass spectrometry. J Chromatogr B Biomed Appl 1996; 678:211-8. [PMID: 8738024 DOI: 10.1016/0378-4347(95)00508-0] [Citation(s) in RCA: 12] [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] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
A method is described for the qualitative and quantitative determination of phenylbutazone and oxyphenbutazone in horse urine and plasma samples viewing antidoping control. A horse was administered intravenously with 3 g of phenylbutazone. For the qualitative determination, a screening by HPLC was performed after acidic extraction of the urine samples and the confirmation process was realized by GC-MS. Using the proposed method it was possible to detect phenylbutazone and oxyphenbutazone in urine for up to 48 and 120 h, respectively. For the quantitation of these drugs the plasma was deproteinized with acetonitrile and 20 microliters were injected directly into the HPLC system equipped with a UV detector and LiChrospher RP-18 column. The mobile phase used was 0.01 M acetic acid in methanol (45:55, v/v). The limit of detection was 0.5 microgram/ml for phenylbutazone and oxyphenbutazone and the limit of quantitation was 1.0 microgram/ml for both drugs. Using the proposed method it was possible to quantify phenylbutazone up to 30 h and oxyphenbutazone up to 39 h after administration.
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Affiliation(s)
- L M Neto
- Antidoping Laboratory, Jockey Club de São Paulo, Brazil
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Salvadori MC, Rieser EM, Ribeiro Neto LM, Nascimento ES. Determination of xanthines by high-performance liquid chromatography and thin-layer chromatography in horse urine after ingestion of Guaraná powder. Analyst 1994; 119:2701-3. [PMID: 7879880 DOI: 10.1039/an9941902701] [Citation(s) in RCA: 21] [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: 01/27/2023]
Abstract
The seeds of Guaraná are rich in xanthines and are used for the preparation of guaraná powder which is very commonly given to horses as a 'tonic' in Brazil. In this paper, the xanthine content of guaraná powder was determined, in addition to its clearance time in horses. Thin-layer chromatography was used as a screening procedure and high-performance liquid chromatography was performed to quantify the drugs in both the powder and urine samples. The guaraná powder was found to contain 2.16, 1.10 and 36.78 mg g-1 of theobromine (TB), theophylline (TP) and caffeine (CF), respectively, and in urine it was possible to detect TB and TP up to 13 d and CF up to 9 d after the administration of guaraná powder.
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Pedroso RC, Salvadori MC, Andraus MH, Lopez NM. Determination of succinonitrile in horse urine by gas chromatography-nitrogen-phosphorus detector and gas chromatography-mass spectrometry. Analyst 1994; 119:2697-9. [PMID: 7879879 DOI: 10.1039/an9941902697] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
A chromatographic method was developed to detect and confirm the presence of succinonitrile (SDN) in horse urine samples, for antidoping control. The urine samples (5 ml) were extracted with diethyl ether and screened by gas chromatography-nitrogen-phosphorus detector and the confirmation of the drug's presence was accomplished by using gas chromatography-mass selective detection. The recovery of extraction was 78 and 81% for 1.0 and 2.0 micrograms ml-1 (relative standard deviation, < 10%), respectively. Urine samples collected after the administration of Energisan were positive for SDN (1-30 h) in all samples analysed.
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Affiliation(s)
- R C Pedroso
- Faculty of Pharmaceutical Sciences, University of São Paulo, Brazil
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Araújo AC, Salvadori MC, Velletri ME, Camargo MM. Influence of furosemide on the detection of flunixin meglumine in horse urine samples. J Anal Toxicol 1990; 14:146-8. [PMID: 2374403 DOI: 10.1093/jat/14.3.146] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [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: 12/31/2022] Open
Abstract
The possibility of false negative results from TLC when a diuretic is administered concomitantly with flunixin was studied. Samples were subjected to solvent extraction from acidic aqueous solutions; duplicate samples were also subjected to alkaline hydrolysis at pH 12.5. The internal standard was flufenamic acid. The quantification of flunixin was performed by HPLC and the results confirmed by GC/MS. The data show that furosemide influences the urinary concentration of flunixin.
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Affiliation(s)
- A C Araújo
- Divisão de Controle e Pesquisas Antidopagem, Jockey Club de São Paulo, Brazil
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Salvadori MC, Velletri ME, Camargo MM, Araújo AC. Identification of doping agents by chromatographic techniques and UV spectrophotometry. Analyst 1988; 113:1189-95. [PMID: 3232828 DOI: 10.1039/an9881301189] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Girardet JP, Beauvais P, Laurent F, Perreve-Genet A, Salvadori MC, Bonnet-Gajdos M. [Sickle-cell cardiomegaly in children. Study of 13 cases]. Arch Fr Pediatr 1983; 40:525-30. [PMID: 6227301] [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: 01/19/2023]
Abstract
Thirteen children, aged 18 months to 14 years and presenting with sickle cell anemia and cardiomegaly (Cardiothoracic ratio greater than or equal to 0.55) were investigated by echocardiography and radio-isotopic measurement of the cardiac output. Eight children presented with one or several criteria of anemic cardiopathy: left ventricular dilatation and hyperkinesia, increased cardiac index. On the contrary, 2 children presented with left ventricular dilatation and decreased contractility, without increase in the cardiac index; 3 children presented with echocardiographic findings similar to those of controls and a normal cardiac index, which is unusual in cases with chronic anemia. These results show that the cardiovascular system of children with sickle cell anemia does not always behave as one would expect in chronic anemia. They also suggest the possible early occurrence of cardiomyopathy, as already described in adults with sickle cell anemia.
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