Publications by authors named "Marcia Graminha"

Leishmaniasis is a neglected tropical disease caused by a protozoan of the genus Leishmania, which has visceral and cutaneous forms. The symptoms of leishmaniasis include high fever and weakness, and the cutaneous infection also causes lesions under the skin. The drugs used to treat leishmaniasis have become less effective due to the resistance mechanisms of the protozoa.

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Leishmaniasis is a neglected disease that remains with a limited number of drugs available for chemotherapy and has an increased drug resistance that affects treatment outcomes. Metal-based drugs such as cyclopalladated complex [Pd(dmba)(μ-N)] (CP2), a Leishmania topoisomerase IB inhibitor involved in calcium dysregulation and mitochondrial dysfunction of the parasite, had been an alternative to outline the appearance of chemoresistance. To identify new molecular targets and point out possible resistance mechanisms, a CP2-resistant Leishmania amazonensis (LaR) was selected by stepwise exposure to increasing drug pressure until a line capable of growth in 13.

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Leishmaniasis is recognized as a serious public health problem in Brazil and around the world. The limited availability of drugs for treatment, added to the diversity of side effects and the emergence of resistant strains, shows the importance of research focused on the development of new molecules, thus contributing to treatments. Therefore, this work aimed to identify leishmanicidal compounds using a peptide dimerization strategy, as well as to understand their mechanisms of action.

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The expression and release of cysteine proteases by Leishmania spp. and their virulence factors significantly influence the modulation of host immune responses and metabolism, rendering cysteine proteases intriguing targets for drug development. This review article explores the substantial role of cysteine protease B (CPB) in medicinal chemistry from 2001 to 2024, particularly concerning combatting Leishmania parasites.

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Introduction: Leishmaniasis comprises a complex group of diseases caused by protozoan parasites from the genus, presenting a significant threat to human health. Infection starts by the release into the skin of metacyclic promastigote (MP) form of the parasite by an infected sand fly. Soon after their release, the MPs enter a phagocytic host cell.

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Leishmaniasis refers to a collection of diseases caused by protozoa from the genus. These diseases, along with other parasitic afflictions, pose a significant public health issue, particularly given the escalating number of at-risk patients. This group includes immunocompromised individuals and those residing in impoverished conditions.

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Leishmaniasis is a neglected disease that impacts more than one billion people in endemic areas of the globe. Several drawbacks are associated with the currently existing drugs for treatment such as low effectiveness, toxicity, and the emergence of resistant strains that demonstrate the importance of looking for novel therapeutic alternatives. Photodynamic therapy (PDT) is a promising novel alternative for cutaneous leishmaniasis treatment because its topical application avoids potential side effects generally associated with oral/parenteral application.

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Leishmaniasis is a highly prevalent, yet neglected disease caused by protozoan parasites of the genus . In the search for newer, safer, and more effective antileishmanial compounds, we herein present a study of the mode of action in addition to a detailed structural and biological characterization of [-benzoyl-'-benzyl-″-(4-tertbutylphenyl)guanidine]. X-ray crystallography and extensive NMR experiments revealed that nearly exclusively adopts the conformation stabilized by an intramolecular hydrogen bond.

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Gracilariales is a clade of florideophycean red macroalgae known for being the main source of agar. We present a de novo genome assembly and annotation of Gracilaria domingensis, an agarophyte alga with flattened thallus widely distributed along Central and South American Atlantic intertidal zones. In addition to structural analysis, an organizational comparison was done with other Rhodophyta genomes.

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Leishmaniasis is a neglected disease that affects 12 million people living mainly in developing countries. Herein, 24 new N-oxide-containing compounds were synthesized followed by in vitro and in vivo evaluation of their antileishmanial activity. Compound 4f, a furoxan derivative, was particularly remarkable in this regard, with EC50 value of 3.

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The current treatment of leishmaniasis is based on a few drugs that present several drawbacks, such as high toxicity, difficult administration route, and low efficacy. These disadvantages raise the necessity to develop novel antileishmanial compounds allied with a comprehensive understanding of their mechanisms of action. Here, we elucidate the probable mechanism of action of the antileishmanial binuclear cyclopalladated complex [Pd(dmba)(μ-N)] (CP2) in Leishmania amazonensis.

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Natural products have been largely explored as treatments for leishmaniasis, neglected diseases with few toxic therapeutic options, as scaffolds for the development of new drugs. Herein, derivatives from the aerial parts of (Less.) DC (extract and its fractions) were evaluated against and macrophage cells.

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Leishmaniasis is a group of diseases that have limited and high toxic therapeutic options. Herein, we evaluated the antileishmanial potential and cytotoxicity of hexanic extract obtained from the Antarctic brown alga using bioguided fractionation against and murine macrophages, which was fractionated by SPE, yielding seven fractions (F1-F7). The fraction F6 showed good anti-amastigote activity (IC = 73.

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Leishmaniasis is a serious and neglected disease that affects 14 million people around the World. The currently available drugs for treatment present several drawbacks such as low efficacy and severe side effects, contributing to patients' low compliance. Photodynamic therapy (PDT) is rising as a promising treatment of cutaneous leishmaniasis, mainly considering its topical administration that circumvents any potential adverse effects commonly related to oral/parenteral administration.

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Introduction: The genus Rhodnius in the subfamily Triatominae comprises 20 species, which can transmit Trypanosoma cruzi and Trypanosoma rangeli. Due to the development of molecular techniques, Triatominae species can now be characterized by mitochondrial and nuclear markers, making it possible to verify and/or correct the existing data on these species. The results achieved in this study provide a more detailed and accurate differentiation of the Rhodnius species, helping the establishment of a more appropriate classification.

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Parasitic diseases are a neglected and serious problem, especially in underdeveloped countries. Among the major parasitic diseases, Leishmaniasis figures as an urgent challenge due to its high incidence and severity. At the same time, the indiscriminate use of antibiotics by the population is increasing together with resistance to medicines.

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Since Leishmania parasites exhibit resistance outbreaks to drugs conventionally used in medical treatments, research of new antileishmanial compounds or alternative treatment therapies are essential. A focus of interest has been the implementation of light-based therapies such as photodynamic therapy, where inorganic compounds such as titanium dioxide have shown promising results as drug delivery carriers. In this work, nanoparticles of TiO doped with Zn (TiO/Zn) were synthesized through solution combustion route and with hypericin (HY) in order to enhance its photodynamic activity in the visible light region.

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Recent scientific research has shown the use of chlorin, phthalocyanines, and porphyrins derivatives as photosensitizers in photodynamic therapy in the treatment of various pathologies, including some of the major skin diseases. Thus, the main goal of this critical review is to catalog the papers that used these photosensitizers in the treatment of acne vulgaris, psoriasis, papillomavirus infections, cutaneous leishmaniasis, and skin rejuvenation, and to explore the photodynamic therapy mechanisms against these conditions alongside their clinical benefits.

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Leishmaniasis is a group of diseases caused by protozoan parasites from the genus Leishmania. There are estimated 1.3 million new cases annually with a mortality of 20,000-30,000 per year, when patients are left untreated.

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Visceral leishmaniasis (VL) is fatal if left untreated. Infected dogs are important reservoirs of the disease, and thus specific identification of infected animals is very important. Several diagnostic tests have been developed for canine VL (CVL); however, these tests show varied specificity and sensitivity.

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The World Health Organization (WHO) estimates that more than one billion people suffer from neglected tropical diseases. Leishmaniasis is a widespread disease, affecting 12 million people around the world with about 1–2 million estimated new cases occurring every year. Although pentavalent antimonial drugs are the most frequently prescribed treatments for leishmaniasis, they produce severe side effects, including cardiotoxicity and hepatotoxicity.

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Chagas disease affects between six and seven million people. Its etiological agent, , is classified into six discrete typing units (DTUs). The biological study of 11 strains presented here included four parameters: growth kinetics, parasitemia curves, rate of macrophage infection, and serology to evaluate IgM, total IgG, IgG1, IgG2a, and IgG3.

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N-oxide derivatives compounds such as furoxan and benzofuroxan are promising scaffolds for designing of new antileishmanial drugs. A series of furoxan (1,2,5-oxadiazole 2-N-oxide) (compounds 4a-b, and 14a-f) and benzofuroxan (benzo[c][1,2,5]oxadiazole1-N-oxide) (compounds 8a-c) derivatives were evaluated against in vitro cultured L. infantum promastigotes and amastigotes.

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Leishmaniasis is a disease found throughout the (sub)tropical parts of the world caused by protozoan parasites of the genus. Despite the numerous problems associated with existing treatments, pharmaceutical companies continue to neglect the development of better ones. The high toxicity of current drugs combined with emerging resistance makes the discovery of new therapeutic alternatives urgent.

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