Towards epigenetic regulation of triple-negative breast cancer via ligand-mediated nanoparticles.

Aims: Develop and analyze triple-negative breast cancer targeted nanoparticles loaded with the demethylating agent decitabine. Materials & methods: The polymers were synthesized by ring-opening polymerization of D,L-lactide and formulated into nanoparticles via emulsion-evaporation method. The nanoparticles were characterized by physicochemical analysis as well as in vitro using breast cancer cell lineages. Results & conclusion: The targeted nanoparticles exhibited a hydrodynamic diameter of 75 ± 12 nm, zeta potential -6.3 ± 0.2 mV and spherical morphology, and displayed greater in vitro accumulation into MDA-MB-231 (triple-negative breast cancer cell-line) compared with MCF7 and HB4A cell lineages as verified by fluorescence confocal microscopy and significant demethylating effects via ADAM33 screening by PCR.

Oxygen therapy alternatives in COVID-19: From classical to nanomedicine.

Around 10-15% of COVID-19 patients affected by the Delta and the Omicron variants exhibit acute respiratory insufficiency and require intensive care unit admission to receive advanced respiratory support. However, the current ventilation methods display several limitations, including lung injury, dysphagia, respiratory muscle atrophy, and hemorrhage. Furthermore, most of the ventilatory techniques currently offered require highly trained professionals and oxygen cylinders, which may attain short supply owing to the high demand and misuse. Therefore, the search for new alternatives for oxygen therapeutics has become extremely important for maintaining gas exchange in patients affected by COVID-19. This review highlights and suggest new alternatives based on micro and nanostructures capable of supplying oxygen and/or enabling hematosis during moderate or acute COVID-19 cases.

Chitosan-coated microvesicles: Effect of polysaccharide-phospholipid affinity on decafluorobutane dissolution.

The stability of perfluorinated microvesicles is mainly determined by the presence of interfacial materials and their ability to hinder the gas component diffusibility into the bloodstream. The goal of this study is to increase the persistence of the gaseous-core by introducing chitosan-coated 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) microvesicles, reducing gas diffusion from microvesicles, and increasing for a long time ultrasonic signals. Our hypothesis was based on the irreversible adhesion of chitosan towards DSPC head groups observed in thin-films models. This affinity enhanced the stabilization of gaseous-core microvesicles, in which the polysaccharide effectively reduced the phospholipid phase transition enthalpy from 383±5.5Jmg(-1) for plain to 150±9.7Jmg(-1) for chitosan-coated microvesicles, providing a more stable structure that diminished the gaseous component lost and provided the persistence of intense (19)F-NMR signals after 48h, twice as long compared to plain samples. As a result, stronger and long-lasting ultrasonic signals were produced by the more stable chitosan-containing microvesicles, thus, presenting great potential to increase the diagnostic and therapeutic applications of perfluorocarbon carries.

Hydrophilicity improvement of mercerized bacterial cellulose films by polyethylene glycol graft.

In this work, polyethylene glycol (PEG), of tree distinct molar masses (200, 300 and 400 g mol(-1)), was grafted onto mercerized bacterial nanocellulose (BNCm) and applied to produce nanofilms (BNCm-PEG). The products BNCm-PEG were characterized by NMR and thermal analysis. Solid-state NMR and X-ray diffraction analyses exhibited no significant differences in index of BNCm-PEG derivatives compared to BNCm, indicating that grafting reaction did not modify the BNCm crystalline structure. The apparent contact angle of the films showed that BNCm-PEG films exhibited a pronounced increase in the polar components (BNCm: 8.1 mN m(-1) vs BNCm-PEG400: 29.4 mN m(-1)), and a decrease in dispersive components (BNCm: 41.7 mN m(-1) vs BNCm-PEG400: 35.2 mN m(-1)) of the surface free energy. The BNCm-PEG films were more hydrophilic than BNCm and retained the biocompatibility with L929 fibroblast cells culture.