Publications by authors named "Thaissa Silva"

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women associated with cardiovascular disease and obesity. The possible benefits of omega-3 supplementation in this syndrome have been discussed much. This study is aimed to verify, based on the scientific data published, if there are any benefits in the omega-3 supplementation in the treatment of PCOS and to indicate its possible dosages for the treatment of polycystic ovary.

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5-Nitro-furan nitrones () and 5-nitro-thiophene nitrones () were synthesized in one step. Compounds - had the most potent leishmanicidal activity against intracellular amastigote forms of and (from 0.019 to 2.

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Background: Natural naphthoquinones have shown diversified biological activities including antibacterial, antifungal, antimalarial, and cytotoxic activities. However, they are also compounds with acute cytotoxicity, immunotoxicity, carcinogenesis, and cardio- and hepatotoxicity, and the modification at their redox center is an interesting strategy to overcome such harmful activity.

Objective: In this study, four novel semisynthetic hydrazones, derived from the isomers α- and β- lapachones (α and β, respectively) and coupled with the drugs hydralazine (HDZ) and isoniazid (ACIL), were prepared, evaluated by electrochemical methods and assayed for anticancer activity.

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Chagas disease is caused by the hemoflagellate protozoa Trypanosoma cruzi and is one of the most important neglected tropical diseases, especially in Latin American countries, where there is an association between low-income populations and mortality. The nitroderivatives used in current chemotherapy are far from ideal and present severe limitations, justifying the continuous search for alternative drugs. Since the1990s, our group has been investigating the trypanocidal activity of natural naphthoquinones and their derivatives, and three naphthoimidazoles (N1, N2 and N3) derived from β-lapachone were found to be most effective in vitro.

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We report a sequential C-H iodination/organoyl-thiolation of naphthoquinones and their relevant trypanocidal activity. Under a combination of AgSR with a copper source, sulfur-substituted benzenoid quinones were prepared in high yields (generally >90%). This provides an efficient and general method for preparing A-ring modified naphthoquinoidal systems, recognized as a challenge in quinone chemistry.

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Thirty four halogen and selenium-containing quinones, synthesized by rhodium-catalyzed C-H bond activation and palladium-catalyzed cross-coupling reactions, were evaluated against bloodstream trypomastigotes of T. cruzi. We have identified fifteen compounds with IC/24 h values of less than 2 μM.

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For the first time, a fluorescent lapachone-based BODIPY was synthesised and characterised by NMR and mass spectrometry. Computational and electrochemical aspects, as well as cytotoxic activity and subcellular localisation, were studied. Confocal microscopy experiments indicated that the probe was a specific mitochondria-staining agent.

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This review discusses the state of the art, challenges and perspectives in recent applications of electrochemistry in the life sciences. It deals mainly with the elucidation of molecular mechanisms of drug action, drug design and development, involving electron transfer, pharmaco-electrochemistry (the combination of electrochemical and pharmacological assays), and electrochemical studies of membrane models and drug delivery. It aims to shed light on the question: does electrochemistry really contribute to this area? It includes a general introduction for the use of electrochemistry in the life sciences, with a focus on how electrochemistry can uniquely provide both kinetic and thermodynamic information.

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This review discusses the state of the art, challenges and perspectives in recent applications of electrochemistry in the life sciences. It deals mainly with the elucidation of molecular mechanisms of drug action, drug design and development, involving electron transfer, pharmaco-electrochemistry (the combination of electrochemical and pharmacological assays), and electrochemical studies of membrane models and drug delivery. It aims to shed light on the question: does electrochemistry really contribute to this area? It includes a general introduction for the use of electrochemistry in the life sciences, with a focus on how electrochemistry can uniquely provide both kinetic and thermodynamic information.

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This study reports on the design, synthesis and antiparasitic activity of three new semi-synthetic naphthoquinones structurally related to the naturally-occurring lapachol and lapachone. Of the compounds tested, 3-(3-methylbut-1-en-1-yl)-1,4-dioxo-1,4-dihydronaphthalen-2-yl acetate (1) was the most active against Plasmodium falciparum among both natural and semi-synthetic naphthoquinones, showing potent and selective activity. Compound 1 was able to reduce the in vitro parasite burden, in vitro parasite cell cycle, as well as the blood parasitemia in Plasmodium berghei-infected mice.

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