Publications by authors named "Marina R Tavares"

Liposomes are one of the most important drug delivery vectors, nowadays used in clinics. In general, polyethylene glycol (PEG) is used to ensure the stealth properties of the liposomes. Here, we have employed hydrophilic, biocompatible and highly non-fouling N-(2-hydroxypropyl) methacrylamide (HPMA)-based copolymers containing hydrophobic cholesterol anchors for the surface modification of liposomes, which were prepared by the method of lipid film hydration and extrusion through 100 nm polycarbonate filters.

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Efficient theranostic strategies concurrently bring and use both the therapeutic and diagnostic features, serving as a cutting-edge tool to combat advanced cancers. Here, we develop stimuli-sensitive theranostics consisting of tailored copolymers forming micellar conjugates carrying pyropheophorbide-a (PyF) attached by pH-sensitive hydrazone bonds, thus enabling the tumor microenvironment-sensitive activation of the photodynamic therapy (PDT) effect, fluorescence or phosphorescence. The nanomedicines show superior anti-tumor PDT efficacy and huge tumor-imaging potential, while reducing their accumulation, and potentially side effects, in the liver and spleen.

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Photo/radiosensitizers, such as octahedral molybdenum clusters (Mo), have been intensively studied for photodynamic applications to treat various diseases. However, their delivery to the desired target can be hampered by its limited solubility, low stability in physiological conditions, and inappropriate biodistribution, thus limiting the therapeutic effect and increasing the side effects of the therapy. To overcome such obstacles and to prepare photofunctional nanomaterials, we employed biocompatible and water-soluble copolymers based on -(2-hydroxypropyl)methacrylamide (pHPMA) as carriers of Mo clusters.

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Galectin-3 (Gal-3) participates in many cancer-related metabolic processes. The inhibition of overexpressed Gal-3 by, e.g.

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This paper summarizes the area of biomedicinal polymers, which serve as nanomedicines even though they do not contain any anticancer or antiinflammatory drugs. These polymer nanomedicines with unique design are in the literature highlighted as a novel class of therapeutics called "drug-free macromolecular therapeutics." Their therapeutic efficacy is based on the tailored multiple presentations of biologically active vectors, i.

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The study describes the synthesis, physicochemical properties, and biological evaluation of polymer therapeutics based on -(2-hydroxypropyl)methacrylamide (HPMA) copolymers intended for a tumor-targeted immuno-oncotherapy. Water-soluble linear and cholesterol-containing HPMA precursors were synthesized using controlled reversible addition-fragmentation chain transfer polymerization to reach molecular weight about 2 × 10 g·mol and low dispersity. These linear or self-assembled micellar conjugates, containing immunomodulatory agent cucurbitacin-D (CuD) or the anticancer drug doxorubicin (Dox) covalently bound by the hydrolytically degradable hydrazone bond, showed a hydrodynamic size of 10-30 nm in aqueous solutions.

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-Acetyllactosamine (LacNAc; Galβ4GlcNAc) is a typical disaccharide ligand of galectins. The most abundant members of these human lectins, galectin-1 (Gal-1) and galectin-3 (Gal-3), participate in a number of pathologies including cancerogenesis and metastatic formation. In this study, we synthesized a series of fifteen -(2-hydroxypropyl)methacrylamide (HPMA)-based glycopolymers with varying LacNAc amounts and presentations and evaluated the impact of their architecture on the binding affinity to Gal-1 and Gal-3.

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The present study obtained coated poly(lactic-co-glycolic acid) nanoparticles using the solvent displacement method aiming to evaluate the effect of the polymer concentration in the pharmaceutical formulations' and polymer properties. Nanosuspensions were evaluated by fourier-transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), zeta potential (ZP), thermogravimetric analysis (TGA), X-ray diffraction (XRD) and time-domain nuclear magnetic resonance (TD-NMR). Uniform nanoparticles could be obtained using this method and higher polymer concentrations led to an increase in particle size and negatively charged surfaces were observed.

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Copaiba oleoresin (CPO), obtained from Copaifera landgroffii, is described as active to a large number of diseases and more recently in the endometriosis treatment. In this work, poly(lactic-co-glycolic acid) (PLGA) nanoparticles containing CPO were obtained using the design of experiments (DOE) as a tool to optimize the production process. The nanoparticles optimized by means of DOE presented an activity in relation to the cellular viability of endometrial cells.

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