Double membrane based on lidocaine-coated polymyxin-alginate nanoparticles for wound healing: In vitro characterization and in vivo tissue repair.

The aim of this study was to develop and characterize a double layer biomembrane for dual drug delivery to be used for the treatment of wounds. The membrane was composed of chitosan, hydroxypropyl methylcellulose and lidocaine chloride (anesthetic drug) in the first layer, and of sodium alginate-polymyxin B sulphate (antibiotic) nanoparticles as the second layer. A product with excellent thickness (0.01-0.02 mm), adequate mechanical properties with respect to elasticity, stiffness, tension, and compatible pH for lesion application has been successfully obtained. The incorporation of the drugs was confirmed analysing the membrane cross-sections by scanning electron microscopy. A strong interaction between the drugs and the functional groups of respective polymers was confirmed by Fourier-Transform Infrared Spectroscopy, thermal analysis and X-ray diffraction. Microbiological assays showed a high antimicrobial activity when polymyxin B was present to act against the Staphylococcus aureus and Pseudomonas aeruginosa strains. Low cytotoxicity observed in a cell viability colorimetric assay and SEM analysis suggest biocompatibility between the developed biomembrane and the cell culture. The in vivo assay allowed visualizing the healing potential by calculating the wound retraction index and by histological analysis. Our results confirm the effectiveness of the developed innovative biomaterial for tissue repair and regeneration in an animal model.

Chitosan/pvp-based mucoadhesive membranes as a promising delivery system of betamethasone-17-valerate for aphthous stomatitis.

Mucoadhesive membranes were proposed in this study as drug delivery system for betamethasone-17-valerate (BMV) in the treatment of recurrent aphthous stomatitis (RAS). The membranes were obtained by using the polymers chitosan (CHI) in both presence and absence of polyvinilpyrrolidone (PVP), following the solvent evaporation method. The presence of PVP in the membranes causes significant modifications in its thermal properties. Changes in the thermal events at 114 and 193 °C (related to BMV melting point), and losses in mass (39.38 and 30.68% for CH:PVP and CH:PVP-B, respectively), suggests the incorporation of BMV in these membranes. However, the morphological aspects of the membranes do not change after adding PVP and BMV. PVP causes changes in swelling ratios (>80%) of the membranes, and it is suggested that the reorganization of the polymer mesh was highlighted by the chemical interactions between the polymers leading to different percentages of BMV released ∼40% and ∼80% from CH-B and CH:PVP-B. BMV release profile follows Korsmeyer and Peppas model (n > 0.89) which suggests that the diffusion of the drug in the swollen matrix is driven by polymer relaxation. In addition, the membranes containing PVP (higher swelling ability) present high rates of tensile strength, and therefore, higher mucoadhesion. Moreover, given the results presented, the developed mucoadhesive membranes are a promising system to deliver BMV for the treatment of RAS.

Validation of an UV spectrophotometric assay for the quantification of polymyxin B in solid lipid nanoparticles.

Polymyxins are efficient antibiotic drugs used for the treatment of Gram-negative bacterial infections. These compounds are not absorbed in the gastrointestinal tract and are responsible for serious toxicological effects. In order to enhance their therapeutic effectiveness, decrease the adverse/toxic side effects and promote a sustained release profile, a derivative--polymyxin B sulphate--has been formulated in solid lipid nanoparticles (SLNs) intended for buccal administration. To quantify polymyxin B in the formulation, UV spectrophotometry analysis was applied, validating the analytical methodology by assessing the selectivity, accuracy, precision, linearity, and repeatability. Analyses were performed at 210 nm keeping the samples at 25 degrees C. Results showed that lipid composition of SLNs did not interfere with the polymyxin B spectra. The linearity showed a correlation coefficient of 0.9977 in the range of 5-90 µg/mL. Quantification of polymyxin B by UV spectrophotometry, at 210 nm in SLN formulations, was approved in all analyzed parameters, validating the methodology proposed in this work.

Nanoemulsions and nanoparticles for non-melanoma skin cancer: effects of lipid materials.

Basal cell carcinomas and squamous cell carcinomas are non-melanoma skin cancers reported to be among the most common malignancies, being responsible for high human morbidity. Conventional chemotherapy applied to these conditions shows non-specific targeting, thus severe adverse side effects are also commonly reported. New therapeutic strategies based on nanoparticulates technology have emerged as alternatives for site specific chemotherapy. Among the different types of nanoparticulates, lipid nanoemulsions and nanoparticles have several advantages for topical delivery of poorly soluble chemotherapeutics. These particles show sustained drug release and protection of loaded drugs from chemical degradation. This technology is promising to enhance the intracellular concentration of drugs and consequently reduce the cytotoxicity of skin chemotherapy.

Avaliação da atividade antimicrobiana de extratos vegetais / Evaluation of the antimicrobial activity of vegetal extracts

Especialmente nas últimas décadas, inúmeros esforços têm sido dirigidos para conferir às plantas seu real papel e valor na terapia. Neste estudo foi avaliada a atividade antimicrobiana de extratos secos de Artemisia absinthium L. (losna), Mentha pulegium L. (poejo), Punica granatum L. (romã), Xanthosema violaceum Schott (taioba) e Syzygium cuminii L. (jambolão). Para avaliar a atividade antimicrobiana foi realizado o teste de difusão em ágar, com 15 diferentes microrganismos, utilizando discos impregnados com as dispersões aquosas dos extratos vegetais. A Concentração Inibitória Mínima (CIM) foi determinada para os extratos que apresentaram atividade inibitória. Os resultados mostraram que os extratos de X. violaceum e S. cuminii inibiram, respectivamente, 8 e 6 bactérias. Conclui-se que os extratos de X. violaceum e S. cuminii são capazes de inibir expressivamente o crescimento microbiano.

In the last decades, innumerable efforts have been directed to confer to the plants its real value in the therapy. The aim of this study was to evaluate the antimicrobial activity of dry extracts of Artemisia absinthium L. (wormwood), Mentha pulegium L. (poejo), Punica granatum L. (pomegranate), Xanthosema violaceum Schott(taro) and Syzygium cuminii L. (jambolan). To evaluate the antimicrobial activity the diffusion test in agar was carried through, with 15 different microorganisms, using discs impregnated with aqueous dispersions of the vegetal extracts. For those extracts that had presented inhibitory activity, the calculation of Minimum Inhibitory Concentration was carried out (CIM). The results had shown that the extracts of X. violaceum and S. cuminii had inhibited 8 and 6 bacteria, respectively. What leads to the conclusion that the extracts of X. violaceum and S. cuminii are capable to inhibit the microbial growth.

Estudo da utilização de antimicrobianos e outros fármacos para distúrbios do trato respiratório em pecientes pediátricos hospitalizados / The study of medication in respiratory and antimicrobian treatment in hospitalized pediatrics patients

O tratamento das doenças respiratórias requerem a utilização de antibióticos, corticosteróides e broncodilatadores. Todavia é desejável que, na pediatria, estas medicações sejam restritas e se utilize uma via de administração confortável. O objetivo deste trabalho foi avaliar a utilização dos medicamentos do trato respiratório e antimicrobianos em pacientes pediátricos hospitalizados, por meio da análise de seus prontuários. Os dados foram coletados durante 120 dias, observando-se os medicamentos prescritos, as doses, as vias de administração e as medidas não farmacológicas prescritas. O critério de inclusão na pesquisa foi estar o paciente internado na pediatria, ter na prescrição um antimicrobiano ou medicamento para o trato respiratório. As análises dos 136 prontuários mostrou que 97,06% continham um antimicrobiano, sendo o mais prescrito ampicilina e o fenoterol e ipratrópio como broncodilatadores. Destaca-se que 21,35% das prescrições apresentaram dosagem abaixo do mínimo e em, 21,89% acima do máximo. Embora em 93,75% dos casos tenha havido prescrição de dieta por via oral, 70,59% dos pacientes tiveram prescrição de medicação por via intravenosa. Esses dados revelam o uso de doses subterapêuticas, prescrição excessiva de antimicrobianos e o uso freqüente da via parenteral que encarecem o tratamento, predispõem ao aparecimento de efeitos indesejáveis como superinfecção, prolongando o tempo de permanência no hospital

Reflexão sobre o ensino farmacêutico / Reflection about pharmaceutical education

Este artigo expressa uma preocupação com o ensino farmacêutico baseado nas novas diretrizes curriculares do Conselho Nacional de Ensino. O passado recente priorizou a formação de recursos humanos para as modalidades em detrimento da área privativa do Farmacêutico, a Farmácia em toda sua abrangência. Para não incorrermos no mesmo erro, é necessário desenvolver competências, que possibilitem ao egresso aplicar o conhecimento técnico-científico no contexto social. As novas diretrizes curriculares encerram o ciclo no qual a formação profissional aparecia com o marco divisório das modalidades análises clínicas e indústria. Modelo no qual se concebia a possibilidade de assistência farmacêutica sem conhecimento integral do medicamento não pode ser repetido por uma formação superficialista, segmentada, repleta de atividades técnicas previsíveis e repetitivas e, sobretudo, se conduzido por pessoas sem o preparo necessário ao ensino da atividade. O retorno às atividades primárias do Farmacêutico deve ser precedido pela formação de recursos humanos específicos para a área, o que não acontecerá a longo prazo