RESUMO
Nanostructured lipid carriers (NLC) have emerged as innovative drug delivery systems, offering distinct advantages over other lipid-based carriers, such as liposomes and solid lipid nanoparticles. Benzocaine (BZC), the oldest topical local anesthetic in use, undergoes metabolism by pseudocholinesterase, leading to the formation of p-aminobenzoic acid, a causative agent for allergic reactions associated with prolonged BZC usage. In order to mitigate adverse effects and enhance bioavailability, BZC was encapsulated within NLC. Utilizing a 23 factorial design, formulations comprising cetyl palmitate (solid lipid), propylene glycol monocaprylate (liquid lipid), and Pluronic F68 as surfactants were systematically prepared, with variations in the solid/liquid lipid mass ratios (60:40-80:20%), total lipid contents (15-25%), and BZC concentrations (1-3%). The optimized formulation underwent characterization by dynamic light scattering, differential scanning calorimetry, Raman imaging, X-ray diffraction, small-angle neutron scattering, nanotracking analysis, and transmission electron microscopy (TEM)/cryo-TEM, providing insights into the nanoparticle structure and the incorporation of BZC into its lipid matrix. NLCBZC exhibited a noteworthy encapsulation efficiency (%EE = 96%) and a 1 year stability when stored at 25 °C. In vitro kinetic studies and in vivo antinociceptive tests conducted in mice revealed that NLCBZC effectively sustained drug release for over 20 h and prolonged the anesthetic effect of BZC for up to 18 h. We therefore propose the use of NLCBZC to diminish the effective anesthetic concentration of benzocaine (from 20 to 3% or less), thus minimizing allergic reactions that follow the topical administration of this anesthetic and, potentially, paving the way for new routes of BZC administration in pain management.
Assuntos
Anestésicos Locais , Benzocaína , Portadores de Fármacos , Lipídeos , Benzocaína/administração & dosagem , Benzocaína/química , Anestésicos Locais/administração & dosagem , Anestésicos Locais/química , Anestésicos Locais/farmacocinética , Anestésicos Locais/farmacologia , Portadores de Fármacos/química , Animais , Lipídeos/química , Camundongos , Nanoestruturas/química , Liberação Controlada de Fármacos , Masculino , Nanopartículas/químicaRESUMO
The use of chicken embryos (CEs) as an in vivo experimental model for different pharmaceutical purposes is not a novelty. However, in recent years, the number of reports employing CE to evaluate several parameters, such as the toxicity and efficacy of drugs and/or nanosystems, has increased. Therefore, this review discusses the relevance of CE for drug testing, emphasizing the inoculation routes and the embryonic stages. The challenges to be overcome, as well as some practical recommendations to allow CE to be more explored as a promising in vivo model in drug analyses, are also highlighted.
Assuntos
Galinhas , Embrião de Mamíferos , Animais , Embrião de Galinha , Modelos Animais de Doenças , Detecção do Abuso de SubstânciasRESUMO
BACKGROUND: Oral and oropharyngeal cancer (OPC) is an important cause of morbidity and mortality worldwide. Populations in situations of social vulnerability tend to have higher incidences of cancer, a higher proportion of late diagnosis, greater difficulties in accessing health services, and, consequently, worse prognosis. The aim of this study was to evaluate the relationship between race/skin color and OPC prognosis in Brazil. MATERIAL AND METHODS: This is a cross-sectional epidemiological study using OPC data from the National Cancer Institute between the years 2000 and 2019. The selected variables were: gender, race/skin color, age, education, smoking and alcohol consumption, stage of the disease and disease status at the end of the 1st treatment. RESULTS: 154,214 cases were recorded. Black men, in the 6th decade of life, were the most affected population. Blacks had a lower level of education when compared to non-blacks (p<0.001). Blacks were more exposed to smoking and alcohol consumption (p<0.001). At the time of diagnosis, the black population was at the most advanced stage when compared to non-blacks (p<0.001). At the end of the 1st treatment, more black patients had disease in progression, as well as more black patients died (p<0.001). CONCLUSIONS: Blacks had a worse prognosis for OPC in Brazil. Despite the limitations, these results are important to elucidate the scenario of health disparities in relation to the race/skin color of the Brazilian population.