Publications by authors named "Alessandra Leda Valverde"

Snakebite envenomation is a public health issue that can lead to mortality and physical consequences. It is estimated that 5.4 million venomous snake bites occur annually, with 130,000 deaths and 400,000 amputations.

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Oral squamous cell carcinoma (OSCC) is a worldwide public health problem, with high morbidity and mortality rates. The development of new drugs to treat OSCC is paramount. plant species have shown many biological activities.

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The combination of computational methods and experimental data from Nuclear Magnetic Resonance (NMR) is a considerably valuable tool in the elucidation of new natural product structures and, also, in the structural revision of previously reported compounds. Until recently, only classical statistical parameters were used, for example, linear correlation coefficient (R ), mean absolute error (MAE), or root mean square deviation (RMSD), as a way to statistically "validate" the structure pointed out by experimental NMR spectra. Regarding the resolution of the relative configuration of organic molecules, novel tools were available in the last few years to assist in the NMR elucidation process.

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Porifera, commonly referred to as marine sponges, are acknowledged as major producers of marine natural products (MNPs). Sponges of the genus have attracted much attention over the years. They are widespread in all continents, and several structurally unique compounds have been identified from this species.

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Marine sponges from the Plakinidae family are well known for hosting cytotoxic secondary metabolites and the Brazilian Atlantic coast and its oceanic islands have been considered as a hotspot for the discovery of new Plakinidae species. Herein, we report the chemical profile among cytotoxic extracts obtained from four species of Plakinidae, collected in Fernando de Noronha Archipelago (PE, Northeastern Brazil). Crude organic extracts of Plakinastrella microspiculifera, Plakortis angulospiculatus, Plakortis insularis, and Plakortis petrupaulensis showed strong antiproliferative effects against two different cancer cell lines (HCT-116: 86.

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Bovine mastitis is an infectious disease that affects the mammary gland of dairy cattle with considerable economic losses. Staphylococcus aureus is the main microorganism involved in this highly contagious process, and the treatment is only using antibiotics. Currently, the search for new treatment and/or compounds is still in need due to microbial resistance.

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Functionalized micro- and nano-sized magnetic beads (MBs) have been widely used as versatile supports for proteins, enzymes, and drugs. Immobilized protein on MB surfaces has been successfully applied for ligand fishing assays allowing for direct identification of active ligands from complex mixtures, such as natural products and synthetic libraries. MBs with different properties such as different core compositions, sizes, coatings, and surface modifications are available commercially.

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Background: In Brazil, the Bothrops genus accounts for 87% of registered snakebites, which are characterized by hemorrhage, tissue necrosis, hemostatic disturbances, and death. The treatment recommended by governments is the administration of specific antivenoms. Although antivenom efficiently prevents venom-induced lethality, it has limited efficacy in terms of preventing local tissue damage.

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Article Synopsis
  • The Aedes aegypti mosquito is a primary carrier of arboviruses, and current insecticides are not only toxic to mammals and the environment, but they also have limited effectiveness.
  • Natural products from the Piper genus, particularly the n-hexanic extract of Piper solmsianum and its component eupomatenoid-6, show potential as alternatives for larvicidal treatments.
  • The study found that the extract was highly effective in killing mosquito larvae and identified eupomatenoid-6 as a promising insecticide with low toxicity to human cells.
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Background: The genus Piper L. has the shikimic acid pathway predominantly expressed, biosynthesizing many cinnamic acid derivatives (CAD).

Objective: Neolignans comprise an important class of CAD that exhibit a wide range of pharmacological properties such as antibacterial, antitumor, insecticidal, anti-inflammatory, antioxidant, smooth muscle relaxant, neuroprotective, antiprotozoal and against platelet aggregation factor.

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