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Lipoic acid is a widely studied substance, whose therapeutic effects are related to its antioxidant activity. Our objective was to develop lipoic acid-loaded lipid-core nanocapsules and evaluate their in vitro antioxidant effect against lipid peroxidation induced by ascorbyl free radicals, using soybean lecithin liposomes as the substrate. The nanocapsule suspensions were prepared by interfacial deposition of poly(epsilon-caprolactone) and characterized by particle size and polydispersion index (photon correlation spectroscopy), zeta potencial (eletrophoretic mobility), drug content and encapsulation efficiency (HPLC). The extent of lipid peroxidation was determined (TBARS). The nanostrucutures presented mean diameters of between 191 and 349 nm, zeta potential values from -14.1 +/- 4.5 to -10.4 +/- 0.6, and high lipoic acid encapsulation. A significant increase in the antioxidant activity of lipoic acid was achieved through nanoencapsulation or by increasing its concentration in the formulation. The protection results ranged from 48.9 +/- 3.4 to 57.4 +/- 9.1% for lipoic acid-loaded lipid-core nanocapsules. The lipoic acid release from nanostrucutures significantly decreased with increasing polymer concentration. Also, it was observed an increasing in the antioxidant activity as the lipoic acid release time decreased. The co-encapsulation of lipoic acid with melatonin in lipid-core nanocapsules did not improve the protection against lipid peroxidation. The results obtained demonstrate the optimal concentrations of polymer and lipoic acid in the formulations in terms of enhancing the antioxidant activity. Furthermore, by the strategy applied, it was verified that nanoencapsulation is an efficient alternative to increase the antioxidant effect of lipoic acid, representing a potential approach for therapeutic applications.

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Sodium alendronate, an antiresorptive drug, primarily used in the treatment of osteoporosis was encapsulated in blended microparticles composed of Eudragit S100 and Methocel K15M. The micropowder obtained by spray-drying technique was characterized in terms of its morphology, particle size, encapsulation efficiency and in vitro drug release. In vivo studies were carried out in order to evaluate the pharmacodynamic effect and the ulcerogenic activity of sodium alendronate-loaded microparticles after oral administration in rats. Drug encapsulation efficiency was close to 80% and particle mean diameter of 13.8 microm. SEM analysis showed spherical collapsed shape particles with smooth surface. At pH 1.2, in vitro experiments showed that <10% of the drug was released from the microparticles. At pH 6.8, the microparticles were able to prolong the sodium alendronate release for 12h. In vivo experiments carried out in ovariectomized rats showed bone mineral density significantly higher for the sodium alendronate-loaded microparticles than for the negative control groups. Furthermore, the microencapsulation of the drug showed a significant reduction in the ulcerative lesion index. In conclusion, the blended microparticles are excellent oral carriers for sodium alendronate since they were able to maintain the drug antiresorptive effect and to reduce the gastrointestinal drug toxicity.

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Este trabalho teve como objetivo desenvolver uma metodologia analítica por espectroscopia UV, para doseamento de cumarina em xaropes de Mikania glomerata. A técnica foi baseada na extração da cumarina utilizando solventes como o clorofórmio e hexano. Após a seleção do solvente, o comprimento de onda foi definido através da sobreposição dos espectros da cumarina, metil parabeno, diluição do xarope e solução extrativa do xarope. Foram preparadas curvas analíticas de cinco soluções de cumarina com concentração variando de 0,002 a 0,03 mg/mL. Para análise da exatidão do método, foram preparados três lotes de xarope de Mikania glomerata Sprengel e o teor de cumarina determinado pela técnica espectrofotométrica foi comparado a técnica por cromatografia líquida de alta eficiência. O solvente selecionado para extração foi o clorofórmio, o comprimento de onda 320 nm. A curva analítica apresentou R² de 0,99978, demonstrando linearidade. A comparação estatística do doseamento da cumarina pela técnica espectrofotométrica estudada com a técnica cromatográfica desenvolvida por Celeghini et al. (2001) demonstrou não existir diferenças significativas, indicativo de exatidão da técnica.

A spectrophotometric procedure for coumarin determination in Mikania glomerata Sprengel (guaco) syrup is described in this work. Due to the high number of constituents in guaco syrups, the coumarin was extracted with apolar extractors (chloroform and hexane), in which chloroform was selected, because of its higher capacity of extraction. After the solvent choice, the wavelength at 320 nm, region where there is the lower interference of syrup constituents, was selected. The calibration curve showed linearity, R² of 0.99978. The spectrophotometric assay of coumarin in three samples of Mikania glomerata Sprengel syrup showed accuracy compared with the HPLC method. The results presented suggest that the spectrophotometric method may be useful for the quantitative analysis of coumarin in Mikania glomerata Sprengel syrup.

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Este trabalho avaliou o conhecimento e aceitação das Práticas Não-Convencionais em Saúde (PNCS) por estudantes do curso de Medicina da Universidade do Sul de Santa Catarina (Unisul). A pesquisa realizada foi do tipo descritiva de campo, aplicada na forma direta extensiva por meio de questionários. As perguntas avaliaram o conhecimento e o interesse a respeito de PNCS. Os entrevistados (n = 197) afirmaram conhecer a maioria das PNCS apresentadas no estudo, destacando-se ioga (96,6 por cento), homeopatia (92,9 por cento), chás caseiros (91,9 por cento), acupuntura e orações (88,8 por cento), além de benzedeiras (83,2 por cento), com porcentagem superior a 80 por cento. Ainda que estas práticas não façam parte do currículo atual deste curso, mais de 50 por cento dos alunos afirmaram ter interesse em aprender sobre 10 das 13 PNCS apresentadas neste estudo. Para PNCS como ioga, acupuntura, fitoterapia e orações, mais de 50 por cento dos alunos afirmaram que indicariam ou apoiariam o uso delas por seus pacientes. Concluiu-se que há interesse dos acadêmicos em práticas não-convencionais, bem como evidências da necessidade de inclusão de disciplinas curriculares que abordem as PNCS nos cursos de graduação em Medicina.

The purpose of this work carried out as a descriptive field study was to assess the acceptance of Non-Conventional Health Practices (NCHP) by medical students at the Universidade do Sul de Santa Catarina (UNISUL). The survey was conducted on the basis of direct extensive observation, by applying questionnaires for evaluating the knowledge and interest about NCHPs. The interviewed students (n = 197) claimed to know most NCHPs, especially yoga (96.6 percent), homeopathy (92.9 percent), homemade teas (91.9 percent), acupuncture and prayers (88.8 percent) as well faith healing (83.2 percent), all of which with percentages over 80 percent. Although such practices are not part of the syllabus, more than 50 percent of the students showed interest in learning at least 10 of the 13 NCHPs listed. Besides, more than 50 percent of the students stated that they would recommend or support the use of NCHPs such as yoga, acupuncture, phytotherapy and prayers. It was concluded that the students are interested in non-conventional practices and that disciplines approaching NCHPs should be included in the curriculum of medicine courses.

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